Evolution after Darwin: the University of Chicago Centennial

Digitized by the Internet Arciiive

in 2010 witii funding from

Lyrasis IVIembers and Sloan Foundation

http://www.archive.org/details/evolutionafterda03taxs

EVOLUTION AFTER DARWIN

THE UNIVERSITY OF CHICAGO CENTENNIAL
VOLUME III

ISSUES IN EVOLUTION

SOL TAX AND CHARLES CALLENDER, EDITORS

EVOLUTION

AFTER

DARWIN

THE UNIVERSITY OF CHICAGO CENTENNIAL

VOLUME III

ISSUES

IN
EVOLUTION

THE UNIVERSITY OF CHICAGO
CENTENNIAL DISCUSSIONS

^ THE
UNIVERSITY OF
CHICAGO PRESS

EVOLUTION AFTER DARWIN

THE UNIVERSITY OF CHICAGO CENTENNIAL
VOLUME I

THE EVOLUTION OF LIFE

EDITED BY SOL TAX
VOLUME II

THE EVOLUTION OF MAN 5 1^

EDITED BY SOL TAX

VOLUME III

ISSUES IN EVOLUTION

EDITED BY SOL TAX AND CHARLES CALLENDER

Library of Congress Catalog Number: 60-10575

The University of Chicago Press, Chicago 37

Cambridge University Press, London, N.W. 1, England

The University of Toronto Press, Toronto 5, Canada

© 1960 by the University of Chicago. Published 1960

Printed in the U.S.A.

PREFACE

On November 24, 1859, Charles Darwin at last saw in print the manu-
script over which he had labored for almost a quarter of a century, the
book whose ponderous title has become the familiar Origin of Species.
The world had been waiting, and in a single day the first edition of
1,500 was sold out. One hundred years later, the day was celebrated
as marking one of those events that influence the career of man by
changing his perspective of himself and his place in the universe.

In December of 1955 the University of Chicago began planning its
celebration of the centenary in the most appropriate manner — bringing
to bear, on the subject of evolution, current knowledge from a variety
of relevant fields, thus advancing once more our understanding of the
world and man.

About fifty scientists were selected during 1956, and their themes
were agreed upon; during 1957 and 1958, they prepared and ex-
changed their papers. Armed with new information and insights, all
but five of the authors met at the University on November 22, 1959, to
prepare for panel discussions of the issues in evolution which were to
be held for the public during the five-day Celebration, beginning on
the Centennial of the publication date of Origin of Species. The discus-
sions were based on the papers that had been distributed in advance,
but the papers themselves were not dehvered at the Celebration.

This is the third and final volume of the University's Darwin Centen-
nial publications, collectively called Evolution after Darwin. Most of
the Centennial papers were published earlier this year in the first two
volumes. The Evolution of Life and The Evolution of Man. The pres-
ent volume. Issues in Evolution, includes three papers on the general
topic of science and spiritual values as well as an index for the entire
set; but it is primarily a record of the Celebration itself.

That record opens with the transcript of a televised conversation
among Adlai Stevenson and four Celebration participants, held shortly
before the Celebration began, and foreshadowing many of the issues
that were discussed during the five-day program. Then follow the five

vi • PREFACE

panel discussions that constituted the heart of the Celebration; and Sir
JuHan Huxley's convocation address, a delineation of the evolutionary
vision that knits together many of the varied themes discussed at the
panels; it ultimately became the most controversial event of the Cele-
bration week. An assessment of the panel discussions by three of the
participants forms a fitting postscript to the series. The book closes
with a personal appraisal of the Darwin Centennial Celebration and
its significance by the senior editor, and an album of photographs
by Albert C. Flores which illustrate the program.

The editors of this volume — and Mrs. Marie-Anne Honeywell, the
Conference Secretary — also administered the Celebration, the one as
Chairman of the Committee, and the other as Conference Director.
During the month preceding the Celebration, the Committee members
— Alfred E. Emerson, Chauncy D. Harris, Everett C. Olson, H. Burr
Steinbach, and Ilza Veith — were joined by Sir Julian Huxley and Al-
fred L. Kroeber; all were essential to its success. Others to whom the
Celebration owes much are noted in the proper places.

Sol Tax
Charles Callender

Chicago
July 1960

CONTENTS

EVOLUTION AND RELIGION

A Third Group of Darwin Centennial Celebration Papers

CREATION AND EVOLUTION IN THE FAR EAST 1

Ilza Veith

CURRENT ROMAN CATHOLIC THOUGHT ON EVOLUTION 19

/. Franklin Ewing, S.J.

CREATION AND CAUSALITY IN THE HISTORY
OF CHRISTIAN THOUGHT

Jaroslav Pelikan

29

THE CENTENNIAL CELEBRATION

"at random": a television preview 41

Sir Charles Darwin, Sir Julian Huxley, Harlow
Shapley, Adlai Stevenson, and Sol Tax;
moderated by Irv Kupcinet

introduction to the panel DISCUSSIONS 67

Sol Tax

PANEL one: the ORIGIN OF LIFE 69

Chairmen: Harlow Shapley and Hans Gaffron
Panelists: Sir Charles Darwin, Th. Dobzhansky,

E. A. Evans, Jr., G. F. Gause, Ralph W.

Gerard, H. J. Muller, C. Ladd Prosser

PANEL two: the EVOLUTION OF LIFE 107

Chairmen: Sir Julian Huxley and Alfred E. Emerson
PaneHsts: Daniel I. Axelrod, Th. Dobzhansky, E. B.
Ford, Ernst Mayr, A. J. Nicholson, Everett
C. Olson, C. Ladd Prosser, G. Ledyard
Stebbins, Sewall Wright

vii

via ■ CONTENTS

PANEL three: man AS AN ORGANISM 145

Chairmen: G. G. Simpson and F. Clark Howell
Panelists: Marston Bates, Cesare Emiliani, A. Irving

Hallowell, L. S. B. Leakey, Bernhard

Rensch, C. H. Waddington

PANEL four: the EVOLUTION OF MIND 175

Chairmen: Ralph W. Gerard and Ilza Veith
Panelists: Henry W. B rosin, Macdonald Critchley,
W. Horsley Gantt, A . Irving Hallowell,
Ernest Hilgard, Sir Julian Huxley,
Alexander von Muralt, N. Tinbergen

PANEL five: social and cultural EVOLUTION 207

Chairmen: Clyde Kluckhohn and Alfred L. Kroeber

PaneHsts: Robert M. Adams, Edgar Anderson, Sir

Julian Huxley, H. J. Muller, Fred Polak,

Julian Steward, Leslie A. White, Gordon

R. Willey

CONCLUSION 245

Sol Tax

THE EVOLUTIONARY VISION: THE CONVOCATION ADDRESS 249

Sir Julian Huxley

"all THINGS considered:" a television POSTSCRIPT 263

Robert M. Adams, Sir Julian Huxley, Ilza Veith;
moderated by Alec Sutherland

THE celebration: a PERSONAL VIEW 271

Sol Tax
THE PROGRAM IN PICTURES following page 278

INDEX TO EVOLUTION AFTER DARWIN 283

ILZA VEITH

CREATION AND EVOLUTION IN

THE FAR EAST

The tremendous impact of Darwin's Origin of Species within the sphere
of Western culture is readily understood in view of the need to recon-
cile the facts and implications of evolution with the supernatural ele-
ments in the Judeo-Christian religions. In the Far East, however, nei-
ther the revolutionary significance of the evolutionary principle nor
the violent opposition it engendered could have been fully compre-
hended. A review of the earlier Chinese ideology, which also dominated
the rest of the Far East, reveals certain similarities with early, as well
as post-Darwinian, Western evolutionary concepts. A comparison of
these totally independent streams of thought is pertinent to this Cen-
tennial volume and, at the same time, may shed light upon the recent
events in China's social developments.

China has at various times been credited with the earliest formula-
tion of almost every great thought in the history of ideas; with reference
to evolutionary speculations, there is convincing evidence that its an-
cient philosophers were deeply concerned with these matters. Although
their final conclusions were far removed from ours, the original propo-
sitions are so germane to our subject that they merit closer analysis
than has yet been accorded them. In contrast to the Western world,
the Far Eastern philosophers thought of creation in evolutionary
terms. Nevertheless, the establishment of a theory of creation satis-
factory to them all but terminated further speculation, as it did in the
Judeo-Christian West. For that matter, once concepts of creation had
been formed early in China's recorded history, they remained un-
changed and fundamental throughout the Far East until the introduc-
tion of Western evolutionary theories, and these actually proved con-
siderably less alien to traditional Chinese cosmogonic ideas than to
those of the West.

ILZA VEITH is Associate Professor of Medicine and History at the University of
Chicago. Born in Germany, Dr. Veith received her Ph.D. in the history of medicine
in 1947 from the Johns Hopkins University. Her work is supported by research grant
(M-1563) from the United States Public Health Service, National Institutes of
Mental Health, Bethesda.

2 • ISSUES IN EVOLUTION

The striking feature of the Chinese concept of cosmogony is the
fact that creation was never associated with the design or activity of
a supernatural being, but rather with the interaction of impersonal
forces, the powers of which persist interminably. Tao, the foremost of
these forces, touched every conceivable facet of life and thought. Al-
though it has been defined as "the way," "Tao" is a word with an infinite
variety of meanings, and it has even been termed indefinable, "and in
its essence unknowable." Its concept goes back to remote antiquity,
and it existed long before Lao-Tzu (sixth century B.C.), who was the
spiritual father of Taoism, which later became a separate creed. Lao-
Tzu neither created the word nor gave it significance. But in his Tao-te
Ching he gave to the then existing sporadic conception of the universe
a literary form in which Tao was pre-eminent. His Tao, or "Way," is
the originator of heaven and earth, it is the source of all things. Yet
his "Way" is but a metaphorical expression for the manner in which
things came at first into being out of the primal nothingness and how
the phenomena of nature continue to go on.^

Thus in cosmogony it was held to be the force that had shaped the
universe out of chaos. After creation, it was the key to the mysterious
intermingling of heaven and earth, and it also means the Way and the
Method of maintaining harmony between this world and the beyond,
that is, by shaping earthly conduct to correspond completely with the
demands of the other world.^

That the Chinese were early preoccupied with the phenomena of
nature is readily understood when one recalls that long before Lao-
Tzu and Confucious they derived their livelihood from agriculture.^
The crystallization of this development was expressed by the concept
of Tao. Since the entire universe followed one immutable course
which became manifest through the alternation of night and day,
through the recurrence of the seasons, through growth and decay, man
in his utter dependence upon the universe could not do better than
follow a way which was conceived after that of nature. The only
manner in which he could attain the right Way, the Tao, was by emu-
lating the course of the universe and completely adjusting himself to
it. Thus, through Tao, man saw the universe endowed with a spirit
that was indomitable in its strength and unforgiving toward disobedi-
ence.

Yet the ancient Chinese, although subservient to the universe as

^Otto Franke, "Die Cinesen" in Chantepie de la Saussure, Religionsgeschichte
(Tubingen, 1925), Aufl. 4, Vol. I, pp. 195 ff.
''Heinrich Hackmann, Chinesische Philosophie (Munich, 1927).
'Herbert F. Rudd, Chinese Social Origins (Chicago, 1928), p. 3.

ILZA VEITH: FAR EASTERN IDEOLOGY ■ 3

a whole, realized that within nature itself there was a gradation of
power: the earth was dependent upon heaven. When the fields were
scorched and men waited for rain, when winter lingered and sun was
needed to thaw the frozen earth, man saw that heaven was the more
powerful and therefore made heaven his supreme deity. But Chinese
imagination never personalized this higher being or speculated about
its intrinsic qualities.* Heaven, through its visible manifestations, re-
mained the ruler of the world and united its Tao with that of the earth
in order to complete the yearly cycle of nature; and it was by this ex-
ample that man formed his Tao.^

Because it was from the sky that most natural blessings and catastro-
phes seemed to emanate, heaven was always venerated as the supreme
power, but it was never credited with having created the world. Con-
fucius knew nothing of a God, of a soul, of an unseen world. More-
over, he declared that the unknowable had better remain untouched.
Therefore, mythology has no place in the Chinese concept of creation;
instead, the Chinese have groped toward a more scientific explanation
of cosmogony.® Lieh-Tzu (450-375? B.C.), the oldest author who
proposes a theory of creation, starts from chaos, in which the three
primary elements of the universe — force, form, and substance — were
still undivided. This first stage is followed by a second, the great in-
ception, when force becomes separated; then by a third, the great be-
ginning, when form appears; and a fourth, the great homogeneity,
when substance becomes visible. Then the light and pure substances
rise above and form heaven, the heavier and coarser sink down and
produce the earth.^

This concept of the division of substance into a lighter and a
heavier part is one of the many forms which express the origin of the
important Chinese belief in a dual power. Even though the idea of the
chaos — the first stage of the creation of the world — was later replaced

*WilheIm Grube, Religion and Kultus der Chinesen (Leipzig, 1910), pp. 27-31.

° For a detailed description of the early concepts of the Tao, see J. T. M. de Groot,
Universismus: Die Grundlage der Religion und Ethik, des Staatswesens und der
Wissenschaften Chinas (Berlin, 1918), pp. 1-23.

* Almost one thousand years after the philosophers had formulated their theory of
cosmogony, a myth arose which designated a primeval being by the name of P'an Ku
as the creator of the world. The inventor of this legend was Ko Hung, a Taoist recluse
of the fourth century a.d., the author of Shen hsien chiian, or "Biographies of the
Gods." According to later Chinese writers, the picturesque person of P'an Ku is
said to have been a concession to the popular dislike of, or inability to comprehend,
the abstract. V^hile P'an Ku figured to some extent in folklore, the concept of a per-
sonified creator was never adopted by the educated.

^Lieh-Tzu, Book I, chap. 3. See also Alfred Forke, The World Conception of the
Chinese: Their Astronomical, Cosmological and Physico-philosophical Speculations
(London, 1925), p. 34.

4 ' ISSUES IN EVOLUTION

by the Great Void, the Absolute, and then by the Great Unity or the
Monad, the idea that each of these primary conditions divided into
two and then reunited into one has survived.

The dual power that arose from the primary state was held to be
the instigator of all change, for change was viewed as an expression
of duality, as an emergence of a second out of a first state. The two
components of the dual power were designated as Yin and Yang. The
two characters which stand for Yin and Yang have received a vast
variety of interpretations, but, by analyzing the ideographs themselves,
the original and basic meaning of the characters can be ascertained.
A literal translation of the components that constitute the two char-
acters results in the meaning of "the shady side of a hill" for Yin and
"the sunny side of a hill" for Yang. Other interpretations see Yin and
Yang as two banks of a river, one of which lies in the shade, the other
exposed to the sun. Dr. Otto Franke combines these two interpretations
by stating that Yin represents the river bank that is shaded by a moun-
tain, whereas Yang is that side of the river that is lighted by the sun.
These three interpretations agree on the main issue, namely, that Yin
represents the shady, cloudy element, while Yang stands for the sunny
and clear element.

Since Yin and Yang are supposed to be the primigenial elements
from which the universe was evolved, it was natural that they should
be endowed with innumerable qualities. But if we keep in mind their
original meanings — cloudy and sunny — and their original functions —
that of the creation of heaven and earth — we shall find that many of
the additional connotations are either directly related to, or at least
logically derived from, the original concepts.

Yang stands for sun, heaven, day, fire, heat, dryness, light, and
many other related subjects; Yang tends to expand, to flow upward
and outward. Yin stands for moon, earth, night, water, cold, damp-
ness, and darkness; Yin tends to contract and to flow downward. As
heaven, Yang sends fertility in the form of sun (and rain) upon the
earth; hence heaven's relation to earth is like that of man to wife —
the man being Yang and the wife being Yin. This classification of Yin
and Yang was extended and applied to qualities which no longer bear
a direct relationship to the original meaning of "shady" and "sunny,"
although the relationship can often be logically explained. It would
be impossible to enumerate even a small part of the alternatives that
Yin and Yang have come to represent. Nevertheless, a few examples
showing their extension from the physical to the moral, from the con-
crete to the abstract, may be instructive. Yang: motion, hence life;
Yin: low, hence common. Yang: good-beautiful; Yin: evil-ugly. Fur-

ILZA VEITH: FAR EASTERN IDEOLOGY - 5

ther contrasts are virtue- vice, order-confusion, reward-punishment, joy-
sadness, wealth-poverty, health-disease.

The fact that in these contrasts Yang represented the positive and
Yin the negative side must not be interpreted to mean that Yin was a
"bad" and Yang a "good" principle. It must always be borne in mind
that Yin and Yang were conceived of as one entity and that both to-
gether were ever present. Day changed into night, Hght into darkness,
spring and summer into fall and winter. From these, the most striking
and regular manifestations, it was deduced that all happenings in na-
ture as well as in human life were conditioned by the constantly chang-
ing relationship of these two cosmic regulators. But the general appli-
cation of this ever present duality also led to the realization that
neither of the components ever existed in an absolute state, and the
concept arose that within Yang there was contained Yin and within
Yin there was contained Yang. The following passages, taken from
China's earliest medical text, are illustrative of the importance at-
tributed to these two universal forces:

The principle of Yin and Yang is the basis of the entire universe. It is
the principle of everything in creation. It brings about the transformation to
parenthood; it is the root and source of life and death. . . .

Heaven was created by an accumulation of Yang; the Earth was created
by an accumulation of Yin.

The ways of Yin and Yang are to the left and to the right. Water and fire
are the symbols of Yin and Yang, Yin and Yang are the source of power
and the beginning of everything in creation.

Yang ascends to Heaven; Yin descends to Earth. Hence the universe
(Heaven and Earth) represents motion and rest, controlled by the wisdom
of nature. Nature grants the power to beget and to grow, to harvest and to
store, to finish and to begin anew.

The constant interaction of the two basic elements is described in
the following paragraph:

Everything in creation is covered by Heaven and supported by the
Earth. When nothing has as yet come forth the Earth is called: "the
place where Yin dwells"; it is also known as the Yin within the Yin. Yang
supplies that which is upright, while Yin acts as a ruler of Yang.^

While the Tao, the Yin, and the Yang were intangible concepts,
they received expression through their tangible components, the Five
Elements, which must be thought of less as actual substances than as
forces essential to life. In spite of the prevalence of elemental ideas in
early Greek and Indian philosophies, the theory of the five elements is

'Ilza Veith, Huang Ti Nei Ching Su Wen (Baltimore, 1949), p. 15.

6 • ISSUES IN EVOLUTION

no doubt of Chinese origin, and its existence in ancient times is proved
by many old documents. The essence of this ancient tradition is that
Yin and Yang, in addition to exerting their dual power, gave forth
water, fire, metal, wood, and earth. Man, who was said to be the prod-
uct of heaven and earth by the interaction of Yin and Yang, also con-
tains, therefore, the five elements. This close relationship between the
five elements and the human body was also extended to human ac-
tions, since each element was related to a specific emotion, as well as
to a physical sensation.

Despite this apparent emphasis on man's place in the universe, it
must be noted that the Chinese thought that all other animate beings
and inanimate substances were created together with man, in his
image and the image of the universe. All were thought to be regulated
by the same laws, activated by the same dual power, composed of the
same elements, and endowed by the same spirit of life. As was to be
expected, the identity of substantial composition gave rise to the ques-
tion as to whether there was a fixed and permanent hierarchy of things
and beings within the universe. This is reflected in the writings of
Lieh-Tzu (450-375? B.C.), v/ho was mentioned earlier as the first to
concern himself with the theory of creation, and in the writings of
Chuang-Tzu, who lived one century later. In the works of both authors
we find an almost identical description of an extraordinarily imaginative
scale. The similarity between the two accounts raises the question as to
whether Chuang-Tzu borrowed this idea from the earher philosopher or
whether both drew on theories then common in Chinese thought. The
following version is the terser one, presented by Chuang-Tzu: ^

Certain seeds, falling upon water, become duckweed. When they reach
the junction of the land and the water, they become lichen. Spreading up
the bank, they become the dog-tooth violet. Reaching rich soil, they be-
come wu-tsu, the root of which becomes grubs, while the leaves come
from butterflies, or hsii. These are changed into insects, born in the
chimney corner, which look like skeletons. Their name is ch'ii-to. After a
thousand days, the ch'ii-to becomes a bird called kan-yu-kii, the spittle of
which becomes the ssu-mi. The ssu-mi becomes a wine fly, and that comes
from an i-lu. The huang k'uang produces the chiu-yu and the moii-fui pro-
duces the fire-fly. The yang ch'i grafted to an old bamboo which has for a
long time put forth no shoots, produces the ch'ing-ning, which produces the
leopard, which produces the horse, which produces man.^"

It remains undetermined whether this amazing train of thought was
inspired by some observations of nature or whether it simply repre-

®Many of the names in the following quotation could not be identified even by
Chinese commentators.

" Chuang Tzu: Mystic, Moralist, and Social Reformer, trans, from the Chinese by
Herbert A. Giles (2d ed., London, 1926), p. 228.

ILZA VEITH: FAR EASTERN IDEOLOGY ■ 7

sents the brilliant speculation of an imaginative brain. Though com-
pletely fanciful, this ladder of nature is noteworthy because it was
conceived more than two millennia before the Western world began
to re-examine its biblical chronology. But, beyond this, the above-
quoted passage contains two highly important points: first, a belief
in an inherent continuity of all creation and, second, a reference to
the merging of one species into another — from primordial germ to
man. The significance of these implications was analyzed in 1877 by
Ernst Faber, a missionary of the German Lutheran Rheinische Mis-
sions-Gesellschaft, whose Sinological publications were among the
first to deal with the works of Lieh-Tzu. This missionary seems to have
shared the then prevailing German admiration for the new evolution-
ary doctrines, and in Lieh-Tzu's account of the ladder of nature he
even saw "die Darwinsche Hypothese in Chinesischer Gestalt." ^^

While Chuang-Tzu's and Lieh-Tzu's breathtaking journey from
plant-germ to man illustrates a concept of a biological evolution,
somewhat later and more sophisticated philosophers were concerned
with a more careful evaluation of the differences and similarities be-
tween existing orders. This question is treated in considerable detail
in Chu Hsi's magnificent Philosophy of Nature, a compilation of this
philosopher's lectures, which was first brought together soon after his
death in a.d. 1230. It embodies most of the earlier philosophical con-
cepts and strongly influenced later Chinese thinking. Indeed, accord-
ing to its translator, J. Percy Bruce, "On almost every page the
reader will find modes of thought and expression which may be ob-
served among all classes of people, from peasants to literati." ^^ Since
Chu Hsi was doubtless one of China's greatest minds, his views on
"The Nature in Man and Other Creatures" are entirely representative
of Chinese ideas on the subject. Like the one quoted here, many of
his lectures took the form of dialogues which permitted greater em-
phasis on important questions:

1 . Question. Do the Five Agents [the five elements] receive the Supreme
Ultimate equally?

Answer. Yes, equally.

Question. Does man embody all the Five Agents, while other creatures
receive only one?

Answer. Other creatures also possess all the Five Agents, but receive
them partially.

2. Question. What is your opinion of the [Confucian] statement that the
Nature consists of Love, Righteousness, Reverence, and Wisdom?

" Lieh-Tzu, Der Naturalismus bei den alten Chinesen . . . Licius, transl. and an-
notated by Ernst Faber (Elberfeld, 1877), p. 8.

"^ Chu Hsi, The Philosophy of Human Nature, trans, from the Chinese, with notes,
by J. Percy Bruce (London, 1922), p. xi.

8 • ISSUES IN EVOLUTION

Answer. It corresponds to the saying "Their realization is the Nature."
But preceding this are the stages represented by the statements "The
alternation of the negative and positive modes" and "The law of their
succession is goodness." When the Moral Law of the negative and positive
modes alone existed, and before ever the stage of the creation of man and
other beings was reached, these four principles [Love, Righteousness, Rev-
erence, and Wisdom] were already present. Even the lower orders of life,
such as reptiles, all possess them, but partially and not in their perfection,
on account of the limitations caused by the grossness of the Ether.

3. It is true that in the life of men and other creatures the Nature with
which they are endowed differs from the very beginning in the degree of
its perfection. But even within the differing degrees of perfection there is
the further variation. ^^

Obviously, this question had greatly occupied Chu Hsi's mind, for
he frequently discusses it. It is of interest to note that in the following
passage, however, he refers to "inferior" creatures, while the one
quoted above speaks of "other" creatures:

Just as in the case of the body: within are the five organs and six
viscera, and without are the four senses of hearing, sight, taste, and smell,
with the four limbs, and all men possess them alike; so with the moral
nature: within are Love, Righteousness, Reverence, and Wisdom, and
these are manifested in solicitude, conscientiousness, respectfulness, and
moral insight, and all men possess them; so that in all relationships, such
as those of father and son, elder and younger brother, husband and wife,
friend and friend, sovereign and minister, the same moral sentiments exist.
Even in inferior creatures it is the same, except that in their case these
principles are restricted by the rigidity of form and matter. Nevertheless, if
you study their habits you find that in some particular direction they too
manifest the same principles: they, as well as we, have the affection of
parent and chUd; in their male and female there is the relationship of hus-
band and wife, in their differing ages that of elder and younger brothers, in
the flocking together of those of a class that of friends, and in their leader-
ship that of sovereign and minister. It is because all things are produced
by Heaven and Earth, and together proceed from the One Source, that there
is this prevailing uniformity. ^^

The recurrent stress on the compositional equality and behavioral
similarity of all the products of creation gave rise logically to the
question as to the causes and nature of the differences which subse-
quently appeared. These speculations led to evolutionary theories con-
cerning the very beginning of life on earth. Beyond that, however,
thought was not carried. This failure is doubtless due to the intense

" Ibid., pp. 56-57.
^'Ibid., pp. 19-20.

ILZA VEITH: FAR EASTERN IDEOLOGY • 9

veneration for ancient concepts which, once formulated, must be
preserved in their original entirety. However, the very injunctions
to regard ancient writings as eternal and unchangeable verities pro-
vided the basis for reflections on the subject of social and cultural
change. And here the results were surprising. Contrary to Western
ideas such as that expressed by Nietzsche that man is unfinished and
must be refined and completed, mankind, according to Chinese theory,
had completed its social evolution and achieved the highest form of
life at the very dawn of its history. But it was just this very perfection
of social evolution attained so early that resulted in a theory propound-
ing not only stagnation but actual devolution, that inexorably led man
into an imagined state of regression. To establish this fact, recourse
was taken to the impressive device of "priorism," which appears to be
an ancient Chinese practice. This device was also used by Confucius
when he created a picture of antiquity and of ancient rulers which
corresponded — and was supposed to correspond — less to historical
truth than to an ideal estabUshed for the princes and their people. It is
doubtless dangerous to move the ideals of a people into a remote past,
for it interferes with man's normal urge to expect improvement in the
future and to work for it. The tendency to priorism becomes even more
harmful if historical truth about more recent events is cast aside and
a golden age alone is worshiped.

The proponents of the Chinese concept of unequaled perfection
were four legendary rulers, often referred to as the Sages. They are
generally known as Yao, Shun, Yii, and T'ang, although variations of
these names were also used, and they were believed to have lived in
the third millennium B.C. It was the achievement of these figures that
ordered life upon the universe, once creation had taken place. Their
feats are recorded by Mencius, of the fourth century B.C., whose writ-
ings reflect a picture of early social evolution:

In the time of Yao, when the world had not yet been perfectly reduced
to order, the vast waters, flowing out of their channels, made a universal
inundation. Vegetation was luxuriant, the birds and beasts swarmed. The
various kinds of grain could not be grown. The birds and beasts pressed
upon men. The paths marked by the feet of beasts and prints of birds
crossed one another throughout the Middle Kingdom. To Yao alone this
caused anxious sorrow. He raised Shun to office, and measures to regulate
the disorder were set forth. Shun committed to Yi the direction of the fire
to be employed, and Yi set fire to, and consumed, the forests and vegeta-
tion on the mountains and in the marshes, so that the birds and beasts fled
away to hide themselves. Yii separated the nine streams, cleared the courses
of [the rivers] Tsi and Ta, and led them all to the sea. He opened a vent

10 • ISSUES IN EVOLUTION

also for the [rivers] Zu and Han, and regulated the course of the [rivers]
Hwai and Sze, so that they all flowed into the [Yangtze] Chiang. When this
was done, it became possible for the people of the Middle Kingdom to
cultivate the ground and get food for themselves. . . .

The Minister of Agriculture taught the people to sow and reap, cultivat-
ing the five kinds of grain [wheat, glutinous millet, millet, rice, beans].
When the five kinds of grain were brought to maturity, the people all ob-
tained a subsistence. But men possess a moral nature; and if they are well
fed, warmly clad, and comfortably lodged, without being taught at the same
time, they become almost like the beasts. This was a subject of anxious
solicitude to the sage Shun, and he appointed Hsieh to be the Minister of
Instruction, to teach the relations of humanity: — how, between father and
son, there should be affection; between sovereign and minister, righteous-
ness; between husband and wife, attention to their separate functions; be-
tween old and young, a proper order; and between friends, fidelity. The
highly meritorious sovereign said to him, "Encourage them; lead them on;
rectify them; straighten them; help them; give them wings: — thus causing
them to become possessors of themselves. Then follow this up by stimulat-
ing them, and conferring benefits on them.^^

The writings of Mencius were elaborated by many later authors.
From one of these, Han Yii (a.d. 767-824) of the T'ang Dynasty,
we receive an even more detailed description of the evolution of social
structure in China. Since it is of particular significance to our subject,
it will be quoted here in its entirety:

In former times the population was made up of four classes, the scholars,
farmers, artisans and merchants. Now there are six [the four previous ones
plus the Buddhist priests and the Taoist monks]. Formerly there was one
school of [philosophical] precepts [Confucianism]. Now there are three
[Confucianism, Taoism, and Buddhism]. [In reality] there is one class of
food producers and six classes who eat the produce; there is one class of
artisans and six classes who use the objects made by them; there is one
class of merchants and six classes who buy from them. How does one expect
the people not to become impoverished and destitute?

In primitive times, many dangers [threatened] man. But there appeared
the Sages who made themselves known and subsequently taught them the
rules of livmg together [family relations] and to raise [children]; and they
gave them princes and masters [teachers]; they chased [away] the insects,
the reptiles, the birds and the animals and installed man in the middle of
the land [upon the earth of China]. [The people were] cold and the Sages
gave them clothing; they were hungry and the Sages gave them food; those
who lived in the trees fell off; those who lived in caves took sick and the
Sages gave them houses or huts; [the Sages] set up for them [the class] of
artisans, for the purpose of furnishing them the tools to use and [that of]

^^ James Legge, The Chinese Classics, Vol. II: The Works of Mencius (Oxford,
1895), pp. 250-252.

ILZA VEITH: FAR EASTERN IDEOLOGY • 11

the merchant to perform the exchange of that which one has for that which
one does not have. [They] gave them the art of heahng and the medicines
to prevent premature deaths, they estabUshed for them the burial rites and
the posthumous offerings in order to prolong affection and attachment,
they gave them the Rites so as to distinguish the ranks [in the social order],
they gave them music so as to vent the repressed feelings; they instituted
for them the power by which to discipline the lazy and the negligent; they
set up for them punishments to distrain the transgressors and the obstinate.
The people deceived one another — [the Sages] initiated for them forms of
contract, seals, weights and measures which could be trusted. The people
fought among each other — [the Sages] gave them fortified towns and ad-
jacent quarters, armor and weapons for their defence. When danger arose
[the Sages] made the necessary preparations for them, when calamity
threatened [the Sages] found ways for them how to avert it.

And now as Lao-tzu says: As soon as the great Sages vanish, there will
be the great thieves. If one breaks the [false?] weights and measures the
people will cease wrangling. . . .

If in antiquity there had not been the Sages, the human race would have
been extinguished long ago. And why? Man does not have feathers, body
hair, scales or turtle shells to help him resist the cold and the heat, and he
has no talons or tusks to fend for his nourishment. Therefore the function
of the prince consists of the giving of orders. The function of the minister
consists in putting the orders of the prince into action and to transmit
them to the people. As to the people, their function is to produce the crops
of rice, hemp and silk, to manufacture tools and [ritual] vessels and to
interchange the wealth of commerce — all of it so as to serve their superiors.
If the prince does not give orders, he loses that which makes him a prince.
If the minister does not put into action the prince's orders and does not
transmit them to the people, he loses that which makes him a minister.
If the people do not produce the crops, the rice, the hemp and the silk, if
they do not manufacture tools and vessels, if they do not interchange the
wealth of commerce in order to serve their superiors — then they will be
punished. ^^

Both IVLencius and Han Yii praise the Sages in exalted terms and
imply the superiority of their personalities and their accomplishments
which preclude any repetition. Other writers, however, go even
further. They picture the accomplishments of these Sages in terms of
such high order that, by their very feat of existence, these venerable
personages doomed all subsequent generations to degeneracy and fail-
ure. The following passages from an ancient medical text, again in
dialogue form, are descriptive of such devolutionary thinking:

" Le Kuo-Wen Chinois: Recueil de textes acev introduction et notes par Georges
Margoulies (Paris, 1926), pp. 179-180.

12 • ISSUES IN EVOLUTION

The Yellow Emperor once addressed T'ien Shih, the divinely inspired
teacher: "I have heard that in ancient times the people lived [through the
years] to be over a hundred years, and yet they remained active and did
not become decrepit in their activities. But nowadays people reach only
half of that age and yet become decrepit and failing. Is it because the
world changes from generation to generation? Or is it that mankind is
becoming negligent [of the laws of nature]?"

Ch'i Po answered: "In ancient times those people who understood Tao
[the way of self-cultivation] patterned themselves upon the Yin and the
Yang [the two principles in nature] and they lived in harmony with the
arts of divination.

"There was temperance in eating and drinking. Their hours of rising
and retiring were regular and not disorderly and wild. By these means the
ancients kept their bodies united with their souls, so as to fulfill their
allotted span completely, measuring unto a hundred years before they
passed away.

"Nowadays people are not like this; they use wine as beverage and
they adopt recklessness as usual behaviour. They enter the chamber [of
love] in an intoxicated condition; their passions exhaust their vital forces;
their cravings dissipate their true [essence]; they do not know how to find
contentment within themselves; they are not skilled in the control of their
spirits. They devote all their attention to the amusement of their minds,
thus cutting themselves off from the joys of long [fife]. Their rising and
retiring is without regularity. For these reasons they reach only one half
of the hundred years and then they degenerate.

"In the most ancient times the teachings of the sages were followed by
those beneath them; they said that weakness and noxious influences and
injurious winds should be avoided at specific times. They [the Sages] were
tranquilly content in nothingness and the true vital force accompanied
them always; their vital [original] spirit was preserved within; thus, how
could illness come to them?

"They exercised restraint of their wills and reduced their desires; their
hearts were at peace and without any fear; their bodies toiled and yet did
not become weary.

"Their spirit followed in harmony and obedience; everything was satis-
factory to their wishes and they could achieve whatever they wished. Any
kind of food was beautiful [to them]; and any kind of clothing was satis-
factory. They felt happy under any condition. To them it did not matter
whether a man held a high or a low position in life. These men can be
called pure at heart. No kind of desire can tempt the eyes of those pure
people and their mind cannot be misled by excessiveness and evil.

"[In such a society] no matter whether men are wise or foolish, virtu-
ous or bad, they are without fear of anything; they are in harmony with
Tao, the Right Way. Thus they could live more than one hundred years
and remain active without becoming decrepit, because their virtue was
perfect and never imperiled." ^^

"Veith, op. cit., pp. 97-98.

ILZA VEITH: FAR EASTERN IDEOLOGY • 13

These Sages were exalted above all later speculations as to whether
man was inherently good or evil. They conformed to Confucius' tenets
that man was inherently good and fell into error only through lack of
instruction. But different views are present in the writings of a later
Confucian philosopher, Hsiin Tzu (third century B.C.), who held that
man is inherently evil:

Man's nature is evil. Anciently the Sage Kings knew that man's nature
was evil, partial, bent on evil, corrupt, rebellious, disorderly and without
good government. Hence they established the authority of the prince to
govern man; they set forth clearly the Li [Etiquette, Rites] and justice to
reform him; they established laws and government to rule him; they made
punishments severe to warn him, and so they caused the whole country to
come to a state of good government and prosperity. ^^

This passage shows that the concept of the ancient Sages was more
than abstractly meaningful. It even prepared a way for the solution
of affairs of state brought about by the weakening of the ruler. In
China the form of the political organization was never questioned.
Monarchy was accepted as the natural and inevitable vehicle of
sovereignty. It was the moral foundations on which the monarchy
should be based that were the subject of many philosophical rivalries.
This preoccupation with moral principles rather than with political
forms was characteristic of all Chinese thought and led to the belief
that the moral character of the ruler was the factor which determined
the quality of his government. Not until the revolution of 1911 did
anyone ever advance the view that a change in the form of govern-
ment would help to establish the rule of virtue and benevolence.

On the other hand, the Chinese did not invest the person of the
monarch with the attributes of divinity. Above the king, who was not
a god, was T'ien, "Heaven," or Shang Ti, "The Supreme Ancestor,"
and the earthly sovereign was but his deputy, standing in the relation
of an adopted son who had received the Mandate of Heaven {Tien
Ming), by virtue of which he ruled over the earth. This "Mandate"
was not a patent of divine right, irrevocable and eternal. It was con-
ferred upon a sage king whose virtue had entitled him to act as the
deputy of Heaven. His descendants enjoyed it only so long as their
virtue made them worthy representatives of the Supreme Ancestor. A
tyrant who misruled his kingdom and did not possess the virtues of
love, righteousness, reverence, and wisdom was deprived of the Man-
date of Heaven, and rebellion against his rule was not crime but the
just punishment of outraged Heaven acting through the medmm of
the rebels. The above-quoted passage from Han Yu attests to this

"Charles P. Fitzgerald, A Short Cultural History of China (London, 1935), p. 93.

14 • ISSUES IN EVOLUTION

practice, and Mencius, on a famous occasion, when questioned about
the execution of the king by Wu, founder of the Chou Dynasty, de-
nied that this act could be described as the assassination of a prince by
his minister. He replied: "I have heard of the execution of the fellow
Chou [last King of Shang]; I have not heard that a prince was assassi-
nated by a minister." Chou, for his tyranny and crimes, was no longer
fit to be accounted a king. He had lost the Mandate of Heaven which
had already been conferred upon Wu, founder of the next dynasty.
Thus he was "executed," and Wu was not a "minister" or subject, but
the "true King by the appointment of Heaven." ^^

It is interesting that the principle of priorism also invaded the vast
field of Chinese art. As Fitzgerald ^" points out so well, Chinese art,
too, became derivative and increasingly stereotyped. Technical skill
remained at the same high level as that achieved in the T'ang and Sung
periods, but inspiration and originality declined steadily. In bronze
the best Ming workmanship is almost flawless, but it consists of the
mechanical reproductions of ancient pieces decorated with the classi-
cal motifs, and there is a complete lack of invention. When ancient
models were forsaken, the productions of the late bronzesmiths were
insipid and the decoration trivial. The jade and ivory carving of the
Manchu period shows extreme manual skill and delicacy, which main-
tained these ancient arts on a very high technical level down to mod-
ern times. Ivory has perhaps never been wrought into so many intri-
cate forms as by the Cantonese craftsmen, who are able to carve out
of one tusk several spheres, one within the other, all pierced with deli-
cate filigree patterns.

Yet in all these crafts, in spite of the fine workmanship of their prod-
ucts, there is a certain self-consciousness, an absence of real purpose,
which reflects the character of the age in which they were made. These
things, upon which so much skill and patience were expended, were
only intended to please. They had no ritual significance, no hving in-
spiration derived from some ardent belief or high ideal. They were
made for the wealthy as ornaments, to be admired for their technical
perfection or ingenious workmanship, not to be venerated as symbols
of a cult or as the expression of the artist's perception of truth. Ancient
conventions lay heavily upon all the arts, as upon the mind of the edu-
cated class that patronized them.

This archaistic atmosphere was in itself a handicap to evolution.
Just as the Confucianist was taught to look back to a remote classical
age for his criteria of literary style, so the artist took his standards from
the same distant past. The jade carver or bronzesmith was certain to

" Ibid., p. 74.
'"Ibid., pp. 580-81.

ILZA VEITH: FAR EASTERN IDEOLOGY ■ 15

please if he made an exact reproduction of an ancient piece; but if
he struck out a new design, his efforts would be ranked far below the
copy of a classical model. This contempt for all that was not old cre-
ated a sense of inferiority in the artist who tried new forms. It was
accepted as a matter of course that any ancient work was necessarily
superior to anything which could be produced in modern times, and
the artists, succumbing to this psychological pressure, either copied
the past or produced self-consciously trivial work which made no claim
to challenge comparison with antiquity.

It is clear from the foregoing that the Chinese idea of devolution
and the supreme satisfaction with ancient achievement stifled all sub-
sequent developments in the realms of morality, poUtical institutions,
and the arts. Yet this did not preclude isolated advances in certain
aspects of Chinese culture. Entirely new styles in poetry and rhymed
prose were developed and enriched Uterature, in spite of the T'ang
and Sung movements to return to the prose style of the classical times.
In technology the superiority of later methods was perfectly obvious,
and even in philosophy the neo-Confucianists clearly felt that the ideas
of the ancients could be profitably amplified, even if their basic prin-
ciples were good for all times.

Hardly any of these advances, however, ever touched the art of
healing. Its foundation unalterably rested upon the earliest texts and
their universalistic concepts, which saw in the body a microscopic im-
acre of the universe and in the practice of medicine largely a rebalanc-
ing of Yin and Yang and the five elements. Brief flights into rational
medical activity conflicted with hallowed beliefs and were either ac-
tively prohibited, as in the case of surgery, or permitted to fall into
disuse. The latter fate befell the brief practice of inoculation against
smallpox, which was developed in China in the eleventh century, nearly
seven centuries before it was introduced into the West. So complete
was the contentment with the ancient traditions of Chinese heaUng
that to this day it has never been completely supplanted by modern
Western medical science. And, indeed, when first conceived, it was,
like China's culture and social system, a completely rational and work-
able entity, far superior and far more powerful than that of any neigh-
boring people. All further improvement appeared needless.

Thus the grand evolutionary surge that had first carried China so
far in so brief a time was deliberately halted at an arbitrarily set point
of "perfection." With the suspension of all social change, all other evo-
lutionary tendencies were suspended also until it became apparent
that the tenets of the golden age failed to provide safeguards against
a world that had accepted change and took advantage of it. The hu-
mUiation brought about by the Opium War in the middle of the last

16 ' ISSUES IN EVOLUTION I

century and especially, the defeat, in 1895, by fellow- Asians, the Japa--
nese, who had but slightly earlier divested themselves of the strangle-*
hold of priorism triggered the sudden change in Chinese attitudes..
Since its ancient classics were of little avail in China's adjustment to )'
reality, other and foreign sources had to be found to guide her in her 'j
new role of Hving in a world dominated by Western ideas.

One of the first to provide such texts was Yen Fu, in the late nine-
teenth century, who combined a classical Chinese education with
Western studies. In England he had become familiar with the works
of the leading naturalists and philosophers, and he was particularly
struck with the pertinence of T. H. Huxley's writings, which first ac-
quainted him with the theories of the "struggle for existence" and
"survival of the fittest." He undertook the translation of Evolution
and Ethics in 1896. Immediately upon its publication in 1899, it be-
came one of the most influential textbooks in Chinese education. One
of the reasons for the great impact of Yen Fu's translation was his use
of the classical style as well as the introduction of many illustrations
and quotations from classical Chinese sources. By doing so, he pre-
sented modern evolutionary conclusions as logical outgrowths of an-
cient Chinese thinking. In general, this made Huxley's ideas immediately
acceptable, although Wu Ju-lun, then head of the faculty of Peking
Imperial University, commented in a letter to Yen: "If you write a
book yourself, you may say what you hke; but if you are translating
Huxley it is more appropriate to use the ancient quotations and illustra-
tions from the West that are in the original work. It seems undesirable
to exchange them for Chinese sayings, since those persons and things
Chinese could not be familiar to Huxley." ^i ^

In Huxley's writings, Darwinism entered China long before the
translation of Darwin's own books. But it was Darwinism, speaking
through Huxley and made to appear organically related to ancient
Chmese thought on evolution, that furnished the intellectual basis
. -^^n^fn'u"'^^^ upheaval beginning with 1911. This was attested
to in 1920 by one of China's most outstanding scholars, Liana Ch'i-
ch'ao, when he wrote : ^

Since Darwin's discovery of the principle of the evolution of species a
great revolution has occurred in inteUectual circles over the whole world
His service to learning must be acknowledged. But afterwards his theory
of the struggle for existence and survival of the fittest was applied to the
study of human society and became the core of thought, with many evU
consequences This great European war has nearly'wiped out human
civilization; although its causes were very many, it must be said that the

" Tsuen-Hsuin Tsien. "Western Impact on China through Translaf,-r>n » J7 r- .
Quarterly. Xm (1954), 321. ^"^"'^ ^"^ougn iranslation, Far Eaj/ern

ILZA VEITH: FAR EASTERN IDEOLOGY ■ 17

Darwinian theory had a very great influence. Even in China in recent
years where throughout a whole country men struggle for power, grasp for
gain 'and seem to have gone crazy, although they understand nothmg of
scholarship, yet the things they say to shield themselves from condemna-
tion are regularly drawn from Yen Fu's translation of T. H. Huxley s
Principles of Evolution. One can see that the influence of theory on men s
minds is enormous. No wonder that Mencius said, "These evils, growmg
in the mind, do injury to government, and displayed in the government,
are harmful to the conduct of affairs." 22

It is interesting that Liang Ch'i-ch'ao in his review of China's progress
nostalgically invoked a saying of Mencius, for he must have been
deeply aware that the bonds with the golden age had been brokeri
forever. The gap of evolutionary thinking of two thousand years had
been firmly closed, and with it evolution itself had carried China to
a destiny which Mencius himself had foretold with dread: "Now here
is this shrike-tongued barbarian of the south, whose doctrines are
not those of the ancient kings. Your conduct is different indeed from
that of the philosopher Tsang." ^^

I am indebted to Professors Edward A. Kracke, Jr., and Tsuen-
hsuin Tsien of the Department of Oriental Languages and Literature,
University of Chicago, for their generous suggestions.

=^ Ssu-yu Teng and John K. Fairbank, China's Response to the West (Cambridge:
Harvard University Press, 1954), p. 267.
''^Legge, op. dr., II, 255.

/. FRANKLIN EWING, S.J.

CURRENT ROMAN CATHOLIC
THOUGHT ON EVOLUTION

I refuse to admit that there is a real conflict in terms of head-on,
ed^e-to-edge opposition between science and religion — much less be-
tween science and theology. The "conflict," the "opposition," has been
that of human beings. On the one side we have had human bemgs
who have had certain experiences and qualities and, on the other, hu-
man beings who have had quite other experiences and qualities. What
these human beings have most often ignored (lost in the heat of the
battle) are such basic facts as the difference in areas for the scientist,
the philosopher, and the theologian. Let me illustrate this difference

briefly. . ^^.

The scientist deals with the facts of the material universe. His great
goal is to spell out the "How" of things. Let us suppose that a recent
study of sexual behavior in the United States was good science (which
it was not). The author finds that there are patterns of male sexual
behavior. Thus far, so good. Let us suppose (as happened in a sub-
sequent study) that the author says thus and so "should" be the case.
The author is jumping from the scientific to the philosophical level,
to the level of analysis of human nature, in this case to ethics. Above
this level is that of revelation, the scientific approach to which is called

"theology." , . ,. r •

This paper deals with a problem precisely in the field of science
and philosophy and theology. The emphasis in our exposition will be
on the last-named area, because of the request of our chairman. But
in dealing with the relationships of Roman Catholic theology with
evolution, I shall not include in my discussion many facets of religion.
These might be awe, moral implications, personal commitment, prayer,
sacrifice, and the I-Thou relationship with God. I shall keep solely
within the bounds of a purely intellectualistic approach.

This may seem somewhat strange to those who think that intel-

FATHER EWING, Associate Professor of Anthropology at Fordham University,
specializes in "applied anthropology with reference to missionary work His studies
of human paleontology and physical anthropology have included field research m
Lebanon and the Philippines.

J9

20 • ISSUES IN EVOLUTION

lectualism and religion are divorced, if not positively antagonistic.
However, as a Catholic, I believe that the intellect, too, is gravely in-
volved in religion. I believe that every Catholic has to make a syn-
thesis of all known truth, no matter whence derived, for his world
view. I believe that truth perceived by science or philosophy is ulti-
mately from God, who is the Author of all truth. Of course, the tran-
scendental source of truth is revelation. But, obviously, any adequate
concept of God would preclude the possibility that truth learned by
a reasonable study of God's universe could ever be in conflict with
truth presented to us by revelation. That God should contradict him-
self is unthinkable.

Although I am also a professional anthropologist, I shall make
no further use of this fact than to take for granted, in this paper, the
scientific validity of the theory of evolution. Speaking, therefore, as
a Catholic priest, I should propose the following three major topics
for my discussion: (1) the structure of behef in the Catholic church,
as an appropriate background for the further exploration of my theme
today; (2) the outlines of the history of Catholic attitudes toward evo-
lution; and (3) the present Catholic position regarding evolution.

The Structure of Belief

For the Catholic, the truths of revelation are contained in what is
technically called "the deposit of faith." This deposit was left by Christ
himself. The Church, as the continuation of the mission of the historical
Christ (what we know as the "Mystical Body of Christ"), guards and
interprets this deposit of faith. It guards it because there can be no
discrepancy between what Christ taught in the beginning and what
the church teaches in each successive age. It interprets it because each
age— nay, each culture— has its own particular difficulties and lan-
guage and circumstances.

The scientific theologian (and theology is a science, although with
sources and methods quite different from those of the natural sciences)
finds that the truths of revelation are not all of the same rank, much
as they may be, for instance, in the mind of a pious peasant.

So we find that some truths are defined. This means that the Church
(in this case by its pope, or an ecumenical council which includes the
pope) has solemnly and precisely spelled out the doctrine in question
Thus, for our future purposes in this discussion, we may note that
the existence of a spiritual soul in man was defined bv the Council
of Vienne (1311-12). ^

Other truths are so clear from Sacred Scripture or from the uni-
versal and continuous belief of Catholics that they are definable. The

EWING: CURRENT ROMAN CATHOLIC THOUGHT • 21

Church defines doctrines only when need arises. Thus there would
be no particular reason to define the doctrine that God is the Creator
of all things outside himself, unless this doctrine were denied in such
a way as to call for a reaction from the Church or unless this statement
were to be included in a definition for completeness' sake. Still other
doctrines are logically derivable from the premises mentioned. Thus
we go down the hierarchy of doctrines until we come to the very
lowest category in scientific theology, the probable theological opin-
ion.

Other witnesses to the deposit of faith, besides Holy Writ, are
notably the Fathers of the Church. These were public teachers of
religion, ecclesiastics and usually bishops, who wrote during the early
centuries of the Christian Era and formed a link between the time
of the Apostles and that of the later church. The fact that they were
public figures means that their teaching was eminently open to in-
spection; and, furthermore, if the Fathers were unanimous in stating
that a certain doctrine was of Catholic faith, this results in a very
high rank for the doctrine in question. Also, they represented the great
body of Catholics of their times, and thus they remind us of the con-
cise formula of St. Vincent of Lerins (fifth century a.d.): "What all
men have at all times and everywhere believed must be regarded as
true [he was speaking of Catholic belief]."

The Church does not define doctrines right and left or daily. Yet,
here and now, in the circumstances of the times, Catholics should be
kept in tune with Christ's doctrine and spirit. They look for guidance
and inspiration to the church. So the church exercises what is known
in Latin as magisterium ordinarium, the day-by-day teaching, which
is adapted to the day and may even be changed as circumstances dic-
tate. The highest and best example of this ordinary teaching function
is to be found in the encyclicals of the popes. The application of revela-
tion to the social problems of the modern world, for example, has
been the work of the encyclicals of Leo XIII, Pius XI, and Pius XII.
In the encyclical the pope does not normally use his prerogative of
infallibility; in other words, he is not defining this or that doctrine.
But, short of this, the encyclical is of the highest authority for the
CathoUc here and now.

Now we come to a consideration that is of prime importance in
our thinking about Catholicism and evolution. This consideration
is the role of the theologians in the actual doctrinal and moral life
of the Church.

We note in the original sources of revelation a certain economy.
Thus, in the Bible, God obviously did not establish an encyclopedia
of all knowledge (it would be a dull world indeed, with no research

22 ■ ISSUES IN EVOLUTION

and no learning, had he done so!). So, in the Book of Genesis, we
find no erudition about paleontology.

Indeed, God did not satisfy our curiosity concerning every possible
subsection and nuance even in the field of religion itself. It seems that
he decided to reveal the essentials, those truths necessary for us so
that we might love him and our neighbor, that we might observe his
Law and achieve our life's goal in him, together with as many other
human beings as possible.

Picture a ship's captain and his ship following a coasthne into port.
He has lighthouses; these are the great truths revealed by God. Close
in, he may use his searchlight to illumine the darker parts of the coast.
The hghthouses are suflficient for him to reach his port; the search-
light is a help, and he would be a fool not to use it when he can. But
the searchlight of reason can never contradict the testimony of the
lighthouses, for the coast (truth) was made by God, who created all.

Just as there was an economy in the original deposit of faith, so,
too, the Church is economical today. When there is no need of a defini-
tion or even of the expression of its ordinary teaching power, it leaves
the matter to its theologians. Who are they, and what is their author-
ity?

The theologians we are referring to are official teachers of theology,
usually in seminaries where priests are trained but not necessarily so,'
whose verbal mstruction and publications are subject to the scrutiny
of the Church. This reminds us of what we said previously about the
Fathers of the Church.

If the church is, as we Catholics believe, the Mystical Body of Christ,
the continuation into our times of the historical Christ, a body whose
guide and informing principle is the Holy Spirit, it could hardly allow
Its official teachers to propose, en masse and for a long time, doctrines
which were wrong.

This concept is different, as you will immediately realize, from what
I may call the "human" or "organizational" aspect of the Church
But the human factor operates to the same effect. Rome is the highly
centralized center of the Church, and its organization includes human
means for supervising theological teaching around the world. Among
these human means are the Congregations, which are committees
of cardinals and others, set up to help the pope in administering the
details of the Church universal. ^

In areas which fall between the lighthouses of revelation, the Church
eaves a great deal to its theologians. The safest course for any Catho-
hc to follow, at any given point in time, is to heed the common teach-
ing of theologians at that time. This is, for the average Catholic, sheer
prudence. The theologians are experts, professionals; the average
Cathohc is not— that is, in the matter of rehgion.

EWING: CURRENT ROMAN CATHOLIC THOUGHT • 23

The phrase we have just employed, "at any given point of time,"
implies the possibility of theologians changing their opinion from
time to time. I imagine the average non-Catholic is puzzled by this.
His Catholic friends (and authoritative Catholic sources) tell him
that Catholic doctrine is unchangeable. In point of fact, the question
of evolution affords us an excellent example of how Catholic theo-
logians could change their opinion, without challenging the immutabil-
ity of CathoUc doctrine. And so we come to the second section of
our paper.

The Historical Background

Let us try to see the situation as it appeared to Catholic theologians
in 1859, with regard to evolution. In addition to experiencing a sense
of shock, in common with many other people, they had three primary
concerns in the forefront of their immediate thinking.

The first primary concern was, of course, the Catholic faith. In-
volved here was the interpretation of certain texts of Scripture, notably
in the Book of Genesis, but also in other books of the Old and New
Testament; also involved were certain propositions of councils and
popes. But let us, for the moment, stay with the Scriptural texts. There
had been no reason, up to 1859, to doubt the literal interpretation
of these texts.

The first and foremost rule of interpretation, laid down by St.
Augustine long before and reiterated in the famous biblical encyclical
{Providentissimus Deus) of Pope Leo XIII in 1893, is that a text
should be regarded as meant hterally, unless reason or necessity make
us realize that it was not so meant. Some texts are obviously meta-
phorical. No one thinks that "The arm of the Lord is not shortened"
reveals the fact that God has a physical arm. Other texts clearly show
what they mean but are examples of the Near Eastern way of express-
ing things. Finally, there are texts of dogmatic value, because they
propound, in language everyone can understand, truths to be believed.

It is of the nature and office of the theologian that he maintain a
well-balanced conservatism. He is not dealing with a new dentifrice
or a new automobile; nor is he the natural scientist who needs the
latest publication. This reminds me of a story about a German-born
Jesuit at Georgetown University, a geophysicist. At a meeting he
attended, a geologist got up and announced that it was high time
that the church bowed to science. Whereupon the Jesuit retorted: "If
the church bowed to science, it would be bowing m every direction
at vunce!"

Obviously, the theologian does not want to be, nor can he be, a
weathervane. It would do religion no good if he plumped for a theory

24 ■ ISSUES IN EVOLUTION

today, only to have to recant tomorrow. There are those who thmk
that the theologian was too slow to accept the evolution of man's body.
May I remind them that the scientific evidence at the tune of the publi-
cation of Origin of Species, and much later, was scant indeed? I am
referring to the evidence with regard to human evolution and the evi-
dence as derived from the probative source, namely, paleontology
of this there was effectively none in 1859. There was Engis and Gi-
braltar and Neanderthal, but no one knew what to do with them I
admit that there was plenty of evidence from all sorts of sources for
evolution m general, but not for man.

It is difficult for us today to realize this. More human fossils have
been unearthed in the last twenty-five years than in the whole pre-
vious history of the world. But, at any given point in time, the theo-
logian who asked the scientist for good and certain reasons why he
should change his interpretation of a text of Scripture was more often
than not met by conflicting opinions, of which, professionally, the
theologian was not a good judge.

The weaknesses in Darwin's theory of natural selection, not vet
strengthened by modern knowledge of mutations and genetics, were
aU the more confusing to the theologian, especially as there was an
unfortunate tendency to equate Darwin's specific theory with the
overall theory of evolution itself . ^

TTie third primary concern of the theologian, in 1859 as now was

he total membership of the church. The "church is made up c^f aU

sorts of people-scientists, theologians, philosophers, litterateurs and

peasams, pirates, and ordinary folks. While there is no questTon of

thVrT^T' ''"^f.^ '"^^^^"^' "-ertheless the theolo^an (and

board "tnd'' '" ''^"\'' P'"P^^' '' ^^^ P^^^^^ g«^^' "?cros the
board. And-an eminently anthropological consideration because
It involves the mtegration of culture-the theologian has to think of

inf v' "^u' "^^ ^'^"'^ °^ ^^^^"^^°" "«t ^^ something ocurri^
m a vacuum but as part and parcel of what is going on in the worM

:^^S ^Sr^' --'''' ^'-^''- -" as in t^^
From the beginning, Catholic writers made it clear that a soiritual
o Go't 'cU? "d^nor"'"-"' '"^ ''""'='" spirit LVSetc;
doSa". (HereTaretL": 7ZZ>S^'^:^ '='''"'"
the same today.) But it was dimZt f T ^'u }^^^^^^^^^ ^^^^

what was proposed af a suttitme fof God, '" "" """ "P^" ^™^

EWING: CURRENT ROMAN CATHOLIC THOUGHT • 25

From the point of view of the organizational, day-by-day opera-
tion of the church, the theologian had only what we call "private
acts" to guide him; these involved requests of Roman authorities that
certain Catholic books approving of evolution be retired from the
market. It is clear that these acts were administrative and were con-
cerned with the opportuneness of the writings, in view of the common
good of the faithful. No such acts have occurred since 1909, although
a goodly number of Catholic writers have expressed opinions favor-
able to evolution.

Where We Stand Today

The historical merges with the actual with the year 1909. In that year
the Pontifical Biblical Commission issued certain decrees about the
interpretation of Genesis, a part of the Old Testament which has di-
rect bearintr on our theological consideration of the evolution of man.
The Biblical Commission was set up in 1902 by Pope Leo XIII.
The decrees of this commission, when approved by the pope, are an
even safer norm for the ordinary Catholic than the teaching of the
theologians, because they are guides even for the theologians.

In spite of the fact that Genesis and the Bible in general were under
heavy fire from such scholars as the higher critics and the modernists,
the decrees of the commission faithfully held to what I may call a
"Catholic moderation," a middle way between two extremes, reject-
ing fundamentalism (which would make every word of the Bible
literally definitive as we understand those words today) and equally
rejecting modernism (which would make of the Bible a set of beauti-
ful and religious sentiments with no particular connection with real-
ity); the commission pointed out that Genesis contained elements of
true' history but that the literary form was not that of a modern his-
tory book. And, indeed, such statements as those concerning the
creatorship of God, the special nature of man, the fall of man from
grace, and the promise of a Redeemer are of essential importance to
Catholicism. Without Christ the Redeemer, there would be not much
point to Christianity.

In an encyclical (Divino afflante spiritu) of Pius XII, issued m
1943, the duty of the Catholic student of Holy Writ to ascertain the
true meaning of a text, in terms of Near Eastern literary ways, was
re-emphasized. Other minor documents of church officials have also
underlined this emphasis.

The most recent ecclesiastical document mentioning evolution is
the encyclical {Humani generis) of Pius XII, promulgated in 1950.
In a small but special section about human evolution, the Pope made

26 ' ISSUES IN EVOLUTION

the following statements, which we shall first list and then comment
on briefly.

1. In any discussion of evolution, the Catholic must take for
granted the spiritual soul of man.

2. Otherwise, such a discussion is left open by the Church.

3. However, such a discussion is for experts in science and the-
ology, and reasons for and against must be gravely weighed. The
Catholic must be ready to submit to the judgment of the Church.

4. People should not take it for granted that evolution is a proved
fact and should not act as if there were no theological reasons for
reserve and caution in their discussions.

Comments on These Points

1. The fact that every human being has a spiritual soul is so basic
to true religion that we are not surprised to find that the Catholic
church has always believed this to be true. The doctrine that God
himself immediately creates each human soul belongs to that group
of dogmas which the church proposes and to deny which would make
the denier a heretic, even though there has never been any special
reason for a formal definition. This is one occasion on which God
has to step in with his primary power, because matter cannot produce
a spiritual soul. ^

2. This statement re-echoes what Catholic theologians have been
saying from the beginning: a true evolution is not in contradiction to
any Catholic dogma.

3. Considering the actual state of affairs today, Pius XII did not
want evolution bandied about on the level, let us say, of the tabloid
Here, I should thmk, he was considering the generality of Catholics'
who could easily misunderstand the distinction between a spiritual-
istic and a materialistic evolution. He also understood the fact that
true ideas may start with the intellectuals but eventually filter down
lo ine masses.

4. There is a difference between the terminoloPv of scholastic
philosophy and theology and that of modem natural scLce am
preparing a special study on the concept of certitude as derived from
the sciences, as compared with the same concept in philosoDhv and
theology. But here and now, I simply wish to st^e that myTLuc
tory remark, describing evolution as a valid scientific theory is not
at variance with the words of Pius XII ^'

o,£"^ "^'' ^'"°'; '^" '°"''''' "^ evolution, is treated in Humani
genens. This is polygemsm, the derivation of mankind from more
than one stock or from a group of original human beings

EWING: CURRENT ROMAN CATHOLIC THOUGHT ■ 27

This for me, offers no problem. Science is in no position to prove
a multiple origin for modem mankind, nor would it necessarily make
any difference to theology if it could indicate a multiple origm, the
offspring of which later fused into a single origin. Science knows noth-
ing of Adam and Eve, considered by Catholic theology as the first
parents of all modern human beings. But science, m the work of
Sewall Wright, of the University of Chicago, recognizes that muta-
tions are fixed only in small populations; indeed, Wright speaks of
the possibility of bottleneck generations, which may be reduced to

a single pair. . . r r^ a

Modern theologians would say this about the origin of man. God
is the Creator of man, body and soul. Whether he used the method
of evolution for the preparation of the human body or created it from
unorganized matter is not of primary importance. In either case he
is the Creator. But even if he used an already formed body, he touched
both body and soul in the creation of man. The changes m the already
organized body may have been so subtle, so much in the philosophical
order I may say, that no method of physical science could observe
them. But, somehow, God raised the body of man to a human plane
and, of course, created the human spiritual soul.

"In the beginning . . . God created heaven and earth ... and
God created man to His own image." This is the primal fact m the
history of mankind.

Epilogue
Catholic thinkers have been, by and large, reserved about evolution.
However, currently, more and more theologians are showing them-
selves favorable to it. One reason for this is extrinsic to the science ot
theology, but exerting a powerful influence on it. This is the piling-up
of evidence, particularly paleontological, which makes human evolu-
tion more and more credible. Intrinsic to theology has been the recent
climate of opinion among Scripture scholars. The old-fashioned de-
pendence on the immediately verbal exegesis has given way to an
appreciation of the "literary form" of Holy Writ. Thus we are becom-
ing increasingly aware of the fact that the human authors of the Bible
used story, parable, and statement in keeping with the cultural dictates
of the Near East; the most important thing, therefore, is to determine
what religious lesson is proposed in any section of the Bible, not as
in a modern scientific textbook, but as in a document which is at once
very human and divine. f n tu

Speaking from personal opinion, I am sorry that all too tew Catn-
olic thinkers have been really coming to grips with evolution. They

28 • ISSUES IN EVOLUTION

could supply the philosophy of evolution with the mentally satisfying
components of God as Creator and final end of all things in the uni-
verse outside himself and God as the Conserver. This latter means
very simply that God is continually creating his creatures — if he were
to withdraw his creative power for a second from you and me and
the worm and the elephant, all would disappear into nothingness. This
means that God created not only all beings but also all potentialities
for evolution and that he works as a basic co-cause with the activities
and development of his creatures.

In the view of Teilhard de Chardin, God is the pole toward which
man is tending, by a convergence of evolution. If I may borrow a
few words from Darwin's Origin of Species, "There is a grandeur in
this view." Man, with his genetic roots in the whole material universe j
from atoms to primates, still has an element of the divine in him This \
latter element was divinized just as far as it possibly could be by the
advent of the Son of God, and his assumption of human nature and
his redemption of fallen human nature. Now man, as both a natural
and a supernatural being, individually and collectively, still evolves—
he still grows and trends toward his ultimate reahzation in God

JAROSLAV PELIKAN

CREATION AND CAUSALITY IN THE
HISTORY OF CHRISTIAN THOUGHT

Seldom in the history of the Christian church have theologians re-
acted as violently to a non-theological book as they did to Charles
Darwin's Origin of Species. Neither the True Word of Celsus nor
The Revolutions of the Heavenly Bodies of Copernicus nor even per-
haps The Communist Manifesto, damaging though they all were to
the cherished beliefs of many Christians, evoked so many wounded
reactions in their own time from so many theologians, bishops, clergy-
men, and Christian laymen. Clearly, Darwin seemed to be a threat
to something central in Christian faith and life. Bishop Wilberforce
and William Jennings Bryan are partly illustrations and partly carica-
tures of a defensiveness that pervaded large portions of the Christian
world during the two generations following Origm of Species.

How are we to explain that defensiveness? Even if the answer con-
fines itself to the area of Christian doctine and ignores the important
psychological, sociological, and cultural factors in the life of the
church that help to account for its defensive stance, the explanation
is not so obvious as either Thomas Huxley and Clarence Darrow or
Samuel Wilberforce and William Jennings Bryan thought it was; for
diverse and even divergent ideas within the broad Christian tradition
found themselves threatened by the doctrine of organic evolution. In
the opinion of many theologians, Darwin threatened the trustworthi-
ness of the Scriptures by casting doubt upon the literal accuracy of
the narratives in the Book of Genesis; but Copernicus had also been
accused of subverting the truth of the Bible. The traditional Christian
definition of the image of God in man seemed to clash with the idea
of his descent from earlier and lower forms of life, but the voyages
of discovery and the beginnings of modern anthropology had already
shaken some of the foundations of the classical Christian interpreta-
tion of the imago Dei. Faith in the direction of divine Providence

JAROSLAV PELIKAN, Professor of Historical Theology at the Divinity School
UniverStv of Chicago has written more than a dozen books on his specialty. In 1959
he wTtSirSlSoO AWngd^ Award for his book. The Riddle of Roman CathoUasm.

29

30 • ISSUES IN EVOLUTION

over nature, as formulated by writers like William Paley in his Nat-
ural Theology, could not stand if Darwin was right; but the rational-
ism which Paley both attacked and shared had already substituted
its own doctrines of historical destiny for the orthodox, largely Au-
gustinian, concept of divine Providence. Darwin's suggestions about
the descent of man appeared to make the Augustinian doctrine of
original sin through the Fall of one human couple untenable, but so
did the various versions of the idea of pre-Adamites that had achieved
some currency during the seventeenth and eighteenth centuries.

All these Christian doctrines, and many others besides, seemed to
lose their moorings when Darwin cut the rope between man and
Adam. One or another of them predominated in the reactions of vari-
ous churchmen to the Darwinian hypothesis. Yet the one fundamental
Christian doctrine to which Darwin seemed to pose the most direct
threat was certainly the doctrine of creation. If evolution was right,
creation was wrong: on this premise, it appears, Huxley and Wilber-
force, Bryan and Darrow were all in agreement. Because that premise
was supported by so motley a community of scholars and orators on
both sides, it seems to deserve some special examination. This essay
IS an examination of what creation meant originally and of the sub-
sequent history of the Christian definition of creation. I shall review
the origms and then look briefly at some of the chief controversies
over the doctrine of creation in the history of Christian thought with
the mtention of suggesting how that doctrine had maneuvered' itself
into a position where the doctrine of evolution was a fundamental
threat. From a study of those controversies it is clear that (under
some providence or other) the Christian idea of creation had managed
by the nineteenth century to emphasize those aspects of biblical and
patristic language to which Darwinism represented a challenae- and
It had meanwhile tended to ignore, or rather to neglect, thoseVpects
of the tradition that theology could maintain regardless of scientific
discoveries about either the origin of species or the descent of man
1 here IS, unfortunately, no history of the Christian doctrine of crea-
lon. The closest approximation to such a history of this doctrine is

Wn f'^l^ """J'^- ""^ "u""^'' ^ ""^'"'^^ ^§^ by 0«o Zockler on the
history of the relations between science and theology— a work which
IS much more balanced than the more familiar and vastly more pa d^
san book by Andrew Dickson White. But even Zockler's erudite
study does not suSiciently document the ambiguity in the very te^
creation," which has been present throughout Judeo-ChristSn h^
tory, apparently ever since creation.

Certainly it has been present at least since the Old Testament Al-
though the story of how God originally fashioned the world and all

PELIKAN: CREATION AND CAUSALITY ■ 31

that is in it comes first in the sequence of the biblical narratives as
we now have them, it is a mistake to interpret this story as the foun-
dation for all the subsequent narratives. Indeed, literary analysis of
the creation stories suggests that they come rather late in the history
of the development of the Old Testament. But whether or not such
analysis is conclusive, it does seem clear, in the apt formulation of
Werner Foerster, that

the primary witness of the Old Testament is [the witness] to the God who
is sovereign over history, the God of Abraham, Isaac, and Jacob, the God
who led The people of Israel out of Egypt through the Red Sea and the
Jordan into the Promised Land, the God who directed the wars of Israel.
The sequence in the Old Testament is not from creation to history, but
vice versa. Thus it is not: "The Creator (subject) is Jahweh (i.e., the God
of Israel)"; but rather "Jahweh (subject) is the Creator."

Therefore, the story or stories of creation in Genesis are not chiefly
cosmogony but the preface to the history that begins with the calling
of Abraham. Genesis is not world history but the history of the cove-
nant people of God. And as the Book of Exodus is interested in
Pharaoh only for his part in the Exodus of Israel and otherwise cares
so little about him that the Pharaoh of the Exodus is still difficult to
identify historically, so the Book of Genesis is interested in "the heav-
ens and the earth" as the stage for the essentially historical, rather
than cosmic, drama it sets out to recount.

The vocabulary of the Bible bears out this literary and theological
conclusion. The verb used for "create" in the first verse of the Bible
is bara. The same verb is used to designate the sovereign action of
God in history in other passages of the Pentateuch (e.g., Exod. 34: 10,
Num. 16:30) — passages which perhaps constitute the earliest in-
stances of bara in biblical Hebrew. All instances of the verb support
this generalization: bara always has God as its subject, never creatures.
The same is true in the New Testament of the verb used to translate
bara, ktizein. Sometimes ktizein refers to the original constitution
of the world; sometimes it refers to an action of God in history, espe-
cially to the coming of the Christ as the "new creation." But always
it refers to an action whose ultimate actor is God, though the action
may take place through created agents. Thus the central meaning of
the biblical words for "create" is divine activity, regardless of when
the "creating" is said to have taken place or how or from what pre-
viously existing materials, if any. The most common verb for "create"
in the Old Testament is not bara at all, but asah; and, although it may
refer also to what men "make" or "do," it is employed both for God's
"making" in the beginning and for his "making" in the processes of
history, particularly of Israel's history.

32 • ISSUES IN EVOLUTION

Whatever the Genesis stories mean by "creation," therefore, must
be, first, part of what the Bible means by the God of the covenant
and, second, part of how the Bible looks at the meaning of the pres-
ent, empirical world. The "God" who is the subject of the verb "cre-
ate" is the God of Abraham, Isaac, and Jacob in the Old Testament,
the Father of our Lord Jesus Christ in the New. The "world" which
is the object of the verb "create" is the world in which Israel lives
now as a creature of that God. Creation, therefore, is not principally
an account of origins, but of dependence. It is not intended to say
primarily how things began, but how they are in relation to God.
The most solemn celebration of creation in the Old Testament is not
the story in Genesis 1-3, but Psalm 104:

Thou dost cause the grass to grow for the cattle, and plants for man to
cultivate, that he may bring forth food from the earth, and wine to gladden
the heart of man, oil to make his face shine, and bread to strengthen man's
heart. These all look to thee, to give them their food in due season. When
thou givest to them, they gather it up; when thou openest thy hand, they
are filled with good things. When thou hidest thy face, they are dismayed-
when thou takest away their breath, they die and return to their dust'
When thou sendest forth thy Spirit, they are created; and thou renewest
the race of the ground.

The Psalmist knows that man must cultivate the earth and squeeze
the grape, but he looks with thanksgiving and reverence to the God
of the covenant who is at work creating here and now through these
very means. °

Similar thanksgiving and reverence are the appropriate response
to Gods creatmg activity as it extends to man in the here and now
Another Psalm declares (Ps. 139:13 ff.):

Thou didst form my inward parts, thou didst knit me together in my
mothers womb. My frame was not hidden from thee, when I was being
Thl'" '""'1' ^"*"f ^^^[y ™"ght in the depths of the earth. Thy eye!
beheld my unformed substance; in thy book were written, every one of
them, the days that were formed for me, when as yet there wa7none of

Obstetrically, the Psalmist was probably not so well informed as we
are; but anyone who has passed from adolescence to maturity knows

m!tin?r^"^T." "M^^t^^^^l gynecological and obstetrical infer!
mation does no dispel but only deepens, the mystery of which the
Psalmist IS speaking. The issue of obstetrical information should not
be permitted to obscure the basic meaning of the Psahn: that the God
of the covenant carries out his creating activity through natural means

PELIKAN: CREATION AND CAUSALITY • 33

and that he is no less the God of the covenant, hence no less worthy
of reverence, for using such means.

From this insight which Israel had discovered — or, as Israel main-
tained, had received by divine self-disclosure — into the ways of God
in history it necessarily followed that neither nature nor history had
ever been without the presence of the divine activity and that there-
fore God was also the initiator of both nature and human history. Thus
it is that the stories of creation take their place in the biblical witness
to the ways of God. The sun would not smite by day, nor the moon
by night, because the God of the covenant was ultimately trustworthy
and had always been so. The story of the creation in six days and the
story of Adam and Eve both belong to the history of how God deals
with those to whom he has bound himself by a covenant and a law.
Hence the origin of the universe and the origin of man are both predi-
cated of the God whom Israel has come to know, through covenant
and law, as the God of mercy and of justice. To the New Testament
this applies, if anything, with even greater force; for here creation,
insofar as it receives any attention at all, is presupposed on the basis
of the Old Testament, ascribed to the God and Father of our Lord
Jesus Christ, and correlated with redemption. Only seldom in either
the Old or the New Testament is the Genesis story referred to as a
causal explanation of man's dependence upon his Creator now. More
often it is read as an account of what goes on every day.

Because the New Testament presupposed creation on the basis of
the Old Testament, there was no controversy about creation so long
as Christianity remained part of Judaism. But soon after it ventured
forth into the Hellenistic Roman world, it found itself obliged to de-
fend the doctrine of creation. Both the apologetic sermons in the Book
of Acts (Acts 14:15; 17:24-28) quote Paul as taking up the defense
of creation when he addressed the "cultured despisers" of Christian-
ity. Significantly, in both sermons he is represented as defending the
original creation and the continuing creation simultaneously. Justin
Martyr, mingling quotations from Plato with the Scriptures, was will-
ing to define creation as the shaping of a matter that was already in
existence. Against the enemies of the faith Justin therefore defended
the rationality of the notion that God was the Creator in this sense
of the word. The earliest-known apology for Christianity, that of
Aristides, declared — according to a very late and rather dubious re-
cension of its text— that God is "the one who arranged all things and
pervades them [ton systeesamenon ta panta kai diakratounta]" This
appears to adumbrate the later distinction between the original crea-
tion and the continuing preservation of the world. The Syrian Church

34 • ISSUES IN EVOLUTION

Father Tatian, who proved to be a heretic (though on other grounds),
wrote that God had first called matter into being and then had fash-
ioned the world from this pre-existent, albeit created, stuff. Other
Fathers — for example, Clement of Alexandria — tried various related
explanations of the relation between the creating activity of God and
matter.

Apparently the first Church Father to assert clearly that creation
was creatio ex nihilo was Theophilus of Antioch. He writes that "they
[the prophets] taught us with one consent that God made all things
out of nothing; for nothing was coeval with God: but He being His
own place, and wanting nothing, and existing before the ages, willed
to make man by whom He might be known; for him, therefore, He
prepared the world." Now the doctrine of creatio ex nihilo may be
implied in the writings of the prophets, as Theophilus claims. But it
is taught explicitly in only two places in the Bible, both of them in
the New Testament (Rom. 4:17; Heb. 11:3). Neither of these places
uses the technical term for "create," ktizein; on the other hand, all
the instances of ktizein appear to ignore the issue of creatio ex nihilo.
Theophilus finds it a necessary corollary to the biblical understand-
ing of creation and sets it forth as such. He even goes on to say a little
later that "matter, from which God made and fashioned the world,
was in some manner created, being produced by God." Faced by the
doctine of certain Greeks that the world, or perhaps matter, was co-
eternal with God and that God was therefore dependent upon the
world, Theophilus declared creatio ex nihilo as proof that the de-
pendency in the relation between God and the world was all in one
direction. So began the identification of creation primarily or exclu-
sively with creatio ex nihilo, which crowded continuing creation out
of the attention of the theologians.

The identification became even more explicit in the man who
shaped much of the theological vocabulary of the Latin-speaking
Christian West, Tertullian. His Treatise Against Hermogenes is a
full-scale refutation of the claim that matter existed before creation
Creation must mean creatio ex nihilo, even though the creation ac-
counts do not say this in so many words:

If God could make all things out of nothing. Scripture could quite well
omit to add that He had made them out of nothing, but it should have
said by all means that He had made them out of matter, if He had done
so; for the first possibility would be completely understandable even if it
was not expressly stated, but the second would be doubtful, unless it were
stated.

In the argumentation of Theophilus and Tertullian— and later on as
we shall see, in the argumentation of Thomas Aquinas— the polemical

PELIKAN: CREATION AND CAUSALITY ■ 35

target of the creatio ex nihilo was one or another Greek doctrine about
the eternity of the world. The implications of this doctrine for the
Christian understanding of creation seemed to require the declara-
tion of creatio ex nihilo. Thus the Christian war against Greek ideas
helped theologians like Tertullian to make the doctrine of creation
primarily, though never exclusively, a question of origins.

What helped to save Tertullian from making creation exclusively
a question of origins ex nihilo was his war against Gnostic ideas, as
represented by Marcion. A deep aversion for the created world of
matter caused Marcion and the Gnostics to separate God the Creator
from God the Redeemer. Marcion taught that these were two sepa-
rate gods. The Creator, of whom the Old Testament speaks, was in-
ferior to the Father of our Lord Jesus Christ. Tertullian quotes the
Marcionites as saying: "Our God, although He did not manifest Him-
self from the beginning and by means of the creation, has yet revealed
Himself in Christ Jesus." Thus Gnosticism taught a radical discon-
tinuity between salvation and creation, including in this latter term
the present empirical world of matter. Consistently carried out, such
a doctrine of discontinuity would have pushed the idea of creation
so far back into history and so far down into matter that the spirit-
ually minded Gnostic would not have to soil himself with creation
at all. In their answer to this denigration of creation, Tertullian and
the other anti-Gnostic Fathers asserted the identity of the Creator
with the Father of Christ. Christ "entered on His ministry with the
very attributes of the Creator." Therefore, the God who acts in his-
tory is the Creator: this fundamental conviction of Israel's faith found
an echo in the church's faith, as patristic theology defended the faith
against Gnosticism. Nevertheless, the root meaning of "creation" was
now creatio ex nihilo.

In the various summaries of the church's faith and of patristic the-
ology, that root meaning took precedence. When the most masterful
of these summaries came to be composed in the thirteenth century,
Christianity was once more contending with the doctrine of the eternity
of the world, revived for it by the skepticism of the Averroists and
by the rediscovery of the physical writings of Aristotle. Seeing in Aris-
totle the most complete documentation of what the unaided human
mind was able to discover about God, man, and the world, Thomas
Aquinas refused to attempt what some of the Church Fathers had at-
tempted. Instead of trying to prove from reason that the world was
a product of divine creation and not coeternal with God, Aquinas
declared that this doctrine, like the doctrine of the divine Trinity,
was a matter not of reason but of revelation. The dependence of the
present empirical world upon God, on the other hand, was part of

36 ■ ISSUES IN EVOLUTION

the system of motions and causes that underlay his celebrated "five
ways"; and thus it belonged to natural theology, not merely to revealed
theology. Here once more the polemical situation compelled a the-
ologian to stress original creation more than continuing creation and
to make creation chiefly a matter of beginnings rather than of de-
pendence.

So one-sided was this stress than Aquinas found it difficult to ap-
ply the word "create" to anything except the original creation at the
beginning. He quotes Augustine as saying that "to make concerns
what did not exist at all, but to create is to make something by bring-
ing it forth from what was already existing." To this quotation Aquinas
opposes the authority of the Glossa ordinaria, which comments upon
Genesis 1:1 with the definition: "To create is to make something
from nothing." Accepting the definition of the Glossa, Aquinas con-
cludes: "Augustine uses the term 'creation' in an equivocal sense, ac-
cording as to be created signifies improvement in things; as when we
say that a bishop is created. This is not the way in which we here
use the term creation, but in the way already stated," namely, as creatio
ex nihilo. In the conflict over creation and in the clarification of what
creation meant, continuing creation was not at issue, but original
creation was. Thus it could be concluded either that continuing crea-
tion was dependent for its validation upon the assertion of original
creation or that the two were quite separate; whichever of these con-
clusions was accepted, the connection between the two, which had
been characteristic of earlier Christian thought and language, was less
prominent than the distinction between them. At the same time, the
Thomistic theory of essence and existence provided a framework within
which both original creation and continuing creation could be formu-
lated.

Although the Protestant Reformers did not articulate their theories
of essence and existence as precisely as Aquinas had, they retained
the traditional understanding of creation. Thus, for Luther, God's
"resting" on the seventh day meant that "God ceased in such a way
that He did not create another heaven and another earth. It does not
denote that God gave up preserving and governing the heaven and
the earth which had already been created. ... He has, therefore,
ceased to establish; but He has not ceased to govern." In his preach-
ing and in his catechisms Luther spoke about the continuing creation,
as did Calvin; but if there is any difference between the Reformers
and their scholastic predecessors over the doctrine of creation, it is
one only of emphasis, due to the more existentialist cast of Reforma-
tion thought. The distinction between creation and preservation, as
weU as the continuity between them, survived the Reformation and

PELIKAN: CREATION AND CAUSALITY ■ 37

became a standard part of the vocabulary employed by the codifiers
of Reformation thought in the Protestant orthodoxy of the seventeenth
century. One of these codifiers, Johann Andreas Quenstedt (1617-
85), summarized the continuity thus:

God preserves all things through a continuation of the action by which
He originally produced things. For the preservation of a thing is, strictly
speaking, nothing else than the continuing production of it; nor do they
[creation and preservation] differ except in their outward designation (per
extrinsecam quandam denominationem) .

It was not, however, through its emphasis upon continuing creation
that the Protestant Reformation helped to shape the doctrine of crea-
tion, but through its emphasis upon history, specifically through its
insistence upon the unrepeatable character of the events in the history
of God's dealing with man. The immediate occasion for this insistence
was the form which the interpretation of the Mass had sometimes
taken in the later Middle Ages. Folk piety said unreflectively — and
learned medieval theology said more carefully, though often not very
much more carefully — that the sacrifice of Christ on Calvary was re-
peated every day in the unbloody sacrifice of the Mass. Even after
the Council of Trent and the theologians who expounded the decrees
of the Council had introduced far greater precision and restraint into
Roman Catholic language about the repeated sacrifice, Protestant the-
ology continued to regard such language as a fundamental distortion
of the New Testament gospel. Protestant theology, therefore, fastened
upon the biblical declarations that what Christ had done was "once
and for all" {ephapax). Therefore, the sacrifice on Calvary neither
could nor should be repeated in the Mass.

For the purposes of this essay the controversy over the "once and
for all" is important because of the parallel that could so easily be
drawn between redemption and creation. God was always the Re-
deemer; but he was this on the ground of an unrepeatable historical
event, the life, death, and resurrection of Jesus Christ. Since Adam
was a type of Christ, as Paul had said in both Romans and I Corin-
thians, the conclusion was readily available: God was always the
Creator; but he was this on the ground of an unrepeatable historical
event, the creation of the universe ex nihilo at a specific time in the
not-too-distant past and the formation of the first human pair from
the dust of the earth. Einmaligkeit, "unrepeatability," was thus predi-
cated of creation in analogy to redemption. To dispute the historicity
of Jesus Christ meant to undermine faith in the unrepeatable redemp-
tion of the human race, which had taken place between a.d. 1 and 33.
By analogy, to question the historicity of Adam and Eve meant to

38 • ISSUES IN EVOLUTION

subvert the Christian doctrine of the unrepeatable creation of the hu-
man race, which had taken place about 4004 B.C.

It is an irony of theological history that the seventeenth century
should have been both the period when this notion was developing
and the period when science and history were fashioning the weapons
for its destruction. The best illustration of this irony was the theo-
logical conflict over deism during the seventeenth and eighteenth cen-
turies. Deism carried to its conclusion the definition of creation as the
original establishment of the universe ex nihilo. It defined God as
the First Cause, but it seemed to define the "first" in First Cause
chronologically. God was a necessary postulate to explain the origin
of things and the enactment of the laws by which things continued
to function, but he had no role in history since the creation — or, in
any case, a smaller role than traditional supernaturaHsm assigned to
him. Orthodox response to deism was mingled with various shades
of orthodox concessions to deism. By defining creation as primarily
the doctrine of unrepeatable origins, Protestant theology made the
deist attack easier and its own defense more difficult. The theory of
"occasionalism," set forth by some Roman CathoHcs and some Prot-
estants under Cartesian influence, was a noble, but somewhat pathetic,
effort to reclaim history as an area for God's intervention. In spite
of it, the net result of the controversy over deism was an impairment
of the doctrine of creation that rendered it largely incapable of copincr
with even pre-Darwinian "evolutionism." ^

This controversy provides the background for the effort of the
great Protestant theologian Schleiermacher (1768-1834) to redress
the balance between original and continuing creation. In his exposi-
tion of Christian doctrine he proposed two theses:

The original expression of this relation, i.e., that the world exists only in
absolute dependence upon God, is divided in Church doctrine into two
propositions— that the world was created by God, and that God sustains
the world. As the Evangelical [Protestant] Church has adopted both doc-
trines but has not in her confessional documents given to either of them
any distinctive character, it behoves us so to treat them that, taken to-
gether, they will exhaust the meaning of the original expression.

Schleiermacher's treatment of them makes clear that he has at least
one eye on the "evolutionism" of his contemporaries, a generation be-
fore Darwm s Origin of Species. His apologetic concern is to present
he Christian faith m a form that will make it palatable to those whose
Weltanschauung has been shaped by scientific rather than by biblical
cosmologies. The accusations of pantheism and subjectivism that have
been directed at Schleiermacher ever since are an indication that nei-

PELIKAN: CREATION AND CAUSALITY • 39

ther his notion of divine immanence in the universe nor his idea of the
relation between faith and fact was shared by the main body of
IChristian theology in the nineteenth century.

I The main body of Christian theology in the nineteenth century
Ifound itself, on the Roman Catholic side, allied with a philosophy
that allowed room for science but not always for new science and, on
the Protestant side, tied to an interpretation of the biblical doctrine
I of creation that ruled out natural processes like evolution as the
means of creation. The various theories of British divines recounted
by Charles Coulston Gillispie could be duplicated and amplified from
' a study of Continental theologians, both Roman Catholic and Prot-
estant. All these theories are important for an understanding of the
theological defensiveness that we have been analyzing; some of them
are important as the immediate sources for the versions of Christian
theology that Darwin learned and that Huxley was to discuss in his
later years. Because of the controversy over Darwinism, these theories
likewise constitute one of the most important chapters in the history of
the Christian doctrine of creation and probably the most important
chapter in the history of the relations or "warfare" between science
and theology. Even the most reactionary theologian today feels obliged
to pay serious attention to scientific explanations of the universe and
of life, even though he may conclude such attention with the claim
that the biblical account of creation gives him all the explanation he

wants or needs.

The historian of ideas must always reckon with the possibility tnat
a philosophical or theological formulation has had its day, however
glorious that day may have been, and that the time has come to return
it to history, to which it now properly belongs. The famous aphorism
of Thomas Huxley, "Extinguished theologians lie about the cradle of
every science as the strangled snakes beside that of Hercules," exag-
gerates the valid historical generalization that theological doctrines are
born and die. More often, of course, they hibernate, to be awakened
by a later thaw in the intellectual and religious climate. Fifty years
ago the apocalyptic language of the New Testament seemed to be its
more bizarre characteristic, the special province of the grotesque sects
along the fringes of the church. Yet that very apocalyptic language,
radically reconceived and reinterpreted, moved near to the center of
Christian attention on the Continent in the period between the world

Something similar may be happening to the Christian doctrine of
creation at the present time, for a variety of reasons both inside and
outside theological circles. Not all these reasons are connected with
science The works of Karl Heim and Teilhard de Chardin are perhaps

40 • ISSUES IN EVOLUTION

the most celebrated instances of how theology has responded to recent
trends in science and in the philosophy of science; but there are many
other illustrations, from quiet corners all over Christendom, that the-
ologians are listening to scientists with seriousness and humility. So
serious and humble are they in their dedication to the task of theology
that they will not let theologians pose as scientists; so deeply do they
believe in the task of science that they will not let scientists pose as i
theologians. Samuel Wilberforce and Thomas Huxley were not the
first, nor yet the last, to confuse these two tasks of the theologian and
the scientist. It seems that the climate is changing. What flowers may
bloom and what fruits may ripen in the new climate is not for this
historian of theology, but for one of his successors, to describe. We
may perhaps let Thomas Huxley prescribe our credo for us as we work
in this climate. At one stage in his intellectual and spiritual evolution,
in 1860, one year after Origin of Species, he enunciated this credo:
"Science seems to me to teach in the highest and strongest manner
the great truth which is embodied in the Christian conception of
entire surrender to the will of God."

"AT RANDOM"
A TELEVISION PREVIEW

Kupcinet: Welcome to "At Random," a program dedicated to
the lively art of conversation. This is Sol Tax, professor of anthropol-
ogy at the University of Chicago. Professor Tax is the originator and
chairman of the Darwin Centennial Celebration, honoring the hun-
dredth anniversary of the publication of Charles Darwin's Origin of
Species. It will be held at the University of Chicago starting Novem-
ber 24. This is Sir Charles Darwin, distinguished theoretical physicist,
mathematician, and population expert, the grandson and namesake
of Charles Darwin. And here is Sir Julian Huxley, the world-famous
biologist and former director-general of UNESCO. He is a grandson
of Thomas Henry Huxley, the noted nineteenth-century scientist who
was one of Darwin's chief supporters during the early years of stormy
controversy that surrounded the theory of evolution. This person, of
course, is Adlai Stevenson, former governor of the state of Illinois
and twice the Democratic party's candidate for the presidency of the
United States. Later this evening we shall have Harlow Shapley, pro-
fessor of astronomy at Harvard University. I am Irv Kupcinet of
the Chicago Sun-Times.

Now that we are celebrating the centennial of Darwin's Origin of
Species, I should like to ask Sir Julian what he thinks have been the
main contributions of the theory of evolution.

Huxley: The first point to make about Darwin's theory is that it is
no longer a theory, but a fact. No serious scientist would deny the fact
that evolution has occurred, just as he would not deny the fact that
the earth goes around the sun. Darwin's great contributions were,
first, gathering enormous masses of detailed facts that did not make
sense unless evolution had occurred and, second, discovering the
principle of natural selection, and so providing a mechanism of evolu-
tion that is intelligible on scientific grounds without calUng in any
external agency.

This abbreviated television broadcast, previewing the coming Darwin Centennial
Celebration, was presented on WBBM-TV, CBS, Chicago, on the evening of Novem-
ber 21, 1959.

41

42 • ISSUES IN EVOLUTION

Stevenson: Is there no longer any resistance to the theory of evo-
lution?

Huxley: Two or three states in your country still forbid the teach-
ing of evolution, and throughout your educational system evolution
meets a great deal of tacit resistance, even when its teaching is perfectly
legal. Muller, the Nobel Prize-winning geneticist, has written an ad-
mirable paper called "One Hundred Years without Darwin Are
Enough," in which he points out how absurd it is still to shrink from
teaching evolution — the most important scientific development since
Newton and, some would say, the most important scientific advance
ever made. Indeed, I would turn the argument the other way around
and hold that it is essential for evolution to become the central core
of any educational system, because it is evolution, in the broad sense,
that links inorganic nature with life, and the stars with earth, and
matter with mind, and animals with man. Human history is a con-
tinuation of biological evolution in a different form.

Stevenson: Why does Muller say "one hundred years without
Darwin"? The theory of evolution has clearly made enormous progress
from the time Darwin started, when it was almost universally disputed,
until now.

Tax: Muller was writing about our high-school system, where evo-
lution is still taught as a vague theory. What would you think of a
schoolteacher who said: "There is a theory that the earth is round,
but, on the other hand, it might be flat; and there are two opinions
about this"? This, in effect, is what a great many high-school biology
teachers say — or, in many schools, find they must say. They call it the
theory of evolution.

Stevenson: They are afraid of getting into trouble with the au-
thorities?

Tax: Either that, or they don't know that evolution is a fact. It is
hard to say which.

Huxley: A bit of both, I suppose.

Darwin: And then, of course, such attitudes are helped by the fact
that every now and then some subtle little point comes up about
which there is quite legitimate disagreement among geneticists. Then
the antievolutionists seize on this argument and say that even the sci-
entists don't agree.

Huxley: But all scientists agree that evolution is a fact. There are

two problems involved here: First, whether evolution has happened

and there is absolutely no disagreement among scientists that it has.
The second problem is how evolution takes place, and here there has
been argument, although we have made enormous progress in under-
standing the process of evolution and the role of natural selection in

AT RANDOM ■ 43

it. Natural selection was a deductive theory, and a wonderful stroke
of genius. And now natural selection has been analyzed and tested.
We have found that it does occur and that it is effective. In certain cases
we have even measured the speed at which it operates.

Stevenson: What was that famous remark of your grandfather's,
Sir Julian, after Wilberforce attacked Darwinism so brutally? As I re-
member, he said he would rather be descended from a monkey than
be a man who used great gifts to obscure the truth. I think Wilberforce
had asked him whether he was descended from a monkey on his
mother's or his father's side.

Huxley: It was something like this: "Is it on your grandfather's
or your grandmother's side that you trace your descent from an ape?"
And then my grandfather was overheard to say, as he slapped his
thigh, "The Lord has delivered him into my hands." He had not
wanted to speak at the meeting, but after that he felt he had to. And
this, so far as I recollect, is what he said: "It seems to me that one has
no reason to be ashamed of having an ape for an ancestor. If there
were an ancestor whom I should feel shame in recalling, it would
rather be a man — a man of restless and versatile intellect — ^who, not
content with success in his own sphere of activity, plunges into scien-
tific questions with which he has no real acquaintance, only to obscure
them by an aimless rhetoric and distract the attention of his hearers
from the real point at issue by eloquent digressions and skilled appeals
to their religious prejudice." After that there was nothing left for
Wilberforce to say.

Stevenson: I must say that there is a fairly disturbing note in there
about the man with no scientific acquaintance who plunges into scien-
tific questions!

Kupcinet: Some years ago, as a working newspaperman, Gover-
nor Stevenson wrote editorials about the Scopes Trial.

Stevenson: My only possible identification with you distinguished
gentlemen. I was on your side at the age of twenty-three, writing edi-
torials denouncing William Jennings Bryan. That was difficult, be-
cause in 1 900 my grandfather had run for vice-president on the same
ticket with Bryan. He always thought Bryan became a little fuzzy as
he grew older.

Darwin: Bryan had a stroke at the trial, didn't he?

Huxley: Yes, and the implications of that are very interesting. If
Darrow had died of a stroke during the trial, it would have been called
an act of God. But nobody has ever said Bryan was killed by divine
wrath.

DARWESf: If you or I were struck by lightning now, Julian, it would
be a very grim business.

44 • ISSUES IN EVOLUTION

Huxley: Yes, indeed. It would go down in history.
Stevenson: I wonder if there is a parallel between the resistance
to teaching about evolution in our schools and the resistance to teach-
ing about Marxism and communism in this country. Until very re-
cently, we practically equated teaching about Marxism (which is ab-
solutely imperative for understanding the Russians) with advocating
subversion. I think we are much more enhghtened now. I don't know
about Great Britain, but certainly we in the United States are now
beginning to realize that, to deal with philosophies, you have to under-
stand them. And the more we study Marxism, the better able we are
to cope with it.

Huxley: Yes. Wouldn't you agree that in the long run we have to
think, not in terms of a head-on collision between two entirely irrec-
oncilable systems, but of finding a way to transcend the conflict in a
larger synthesis. If you look back historically, in the Middle Ages
Islam and Christianity seemed absolutely incompatible.

Darwin: Or Protestantism and CathoHcism during the Reforma-
tion.

Huxley: But the earlier conflict was even more drastic, because it
involved large areas of the world and totally different religions. One
can't say that there is complete reconciliation between Islam and
Christianity even now, but at any rate the religious difference is not
a source of political nor even of violent ideological conflict.
Tax: You achieve coexistence.

Huxley: You reach a new pattern of thought that comprehends
both systems, up to a certain point. And I think the really evolutionary
outlook is able to comprehend many apparently disparate facts and
to reconcile many apparently irreconcilably conflicting ideas.
Kupcinet: Is evolution going on today?

Huxley: As my old friend Joad would have said, it all depends on
what you mean by evolution. Some biologists would restrict the use
of the word to living organisms apart from man. But you would agree,
Charles, that there has been an evolution of the stars and an evolution
of matter. Evolution is a general word, denoting— how would vou
define it? ^

Darwin: Incomplete constancy.

Huxley: No— it's much more definite than that. I once tried to
define evolution m an over-all way somewhat along these lines- a one-
way process, irreversible in time, producing apparent novelties and
greater variety, and leading to higher degrees of organization
Darwin: What is "higher"?

Huxley: More differentiated, more complex, but at the same time
more integrated.

AT RANDOM • 45

Darwin : But parasites are also produced.

Huxley: I mean a higher degree of organization in general, as
shown by the upper level attained.

After the general Darwinian theory of the evolution of prehuman
life was accepted, there were many poorly thought-out attempts to
apply pure Darwinian ideas to human affairs: the struggle for exist-
ence, for instance, must be a good thing; therefore, highly competitive
economic systems were good, war was good, and so on. At one time,
even child labor was justified on such grounds. But the more one looks
into it, the clearer it becomes that man does not operate primarily by
natural selection, because he has a new method for evolving. Man is
able to transmit the results of his experience, his knowledge, his ideas,
cumulatively from generation to generation, which no animal can do.
So human evolution occurs primarily in the realm of ideas and their
results — in what anthropologists call culture — with natural selection
playing a minor role, so that evolution proceeds much faster and is
not always related merely to survival.

Kupcinet: After one hundred years of Darwinism, what future do
you see?

Huxley: For Darwinism or for man?
Stevenson: Darwinism is doing better than man.
Huxley: Darwinism has come of age, so to speak. We are no
longer having to bother about establishing the fact of evolution, and
we know that natural selection is the major factor causing evolutionary
change. Our problems now concern working out in detail how natural
selection operates, defining what we mean by "increase of organiza-
tion," tracing the general trends that appear in the course of evolution,
and so on. Of course, the most striking phenomenon in biological evo-
lution is the emergence of mind out of an apparently mindless universe.
Stevenson: A mindless universe?

Huxley: The emergence of mind from apparently mindless or-
ganisms.

Stevenson: Yes; I understand. Does mind evolve?
Huxley: During the two and one-half billion years of life, mind
becomes noticeable fairly late, with the appearance of well-developed
vertebrates and higher moUusks and insects.

Kupcinet: This is where you and the religionists diverge. Most of
them go part of the way with Darwin and agree that perhaps God
created man out of a number of animals, but they attribute mind and
soul to God alone.

Huxley: Darwinism removed the whole idea of God as the creator
of organisms from the sphere of rational discussion. Before Darwin,
people like Paley with his famous Evidences could point to the human

46 • ISSUES IN EVOLUTION

hand or eye and say: "This organ is beautifully adapted; it has ob-
viously been designed for its purpose; design means a designer; and
therefore there must have been a supernatural designer." Darwm
pointed out that no supernatural designer was needed; since natural
selection could account for any known form of life, there was no room
for a supernatural agency in its evolution.

Kupcinet: But the churches hold that it was God alone who in-
stilled spirit and soul and mind into man.

Huxley: But that, too, is completely contrary to the facts. There
was no sudden moment during evolutionary history when "spirit" was
instilled into life, any more than there was a single moment when it
was instilled into you. I know that certain theological doctrines say
it is suddenly pumped into the human embryo at — isn't it the third
month? — but that is a completely arbitrary theological postulate. I
think we can dismiss entirely all idea of a supernatural overriding
mind being responsible for the evolutionary process.

Darwin : I do, entirely.

Huxley: And biologists do, with very few exceptions.

Shapley {who had just joined the panel): Julian, earlier this day
I gave a talk of fifty minutes on exactly this same subject — science and
religion. You spoke of their parting. But there are many kinds of re-
ligions. I have had much contact with the liberal clergy of America
in the last two or three years; and they accept evolution, without ob-
jecting to it or worrying about it. And in that famous address in 1951
the Pope went along with evolution.

Huxley: He still said there must be a God who is somehow re-
sponsible in some way, didn't he?

Shapley: Well, he didn't deny God, no. And you don't, either.

Huxley: I certainly do.

Shapley: Oh, no. If you defined God, you wouldn't.

Huxley: Now don't go into semantics.

Shapley: You're not an atheist, Julian; you're an agnostic.

Huxley: I am an atheist, in the only correct sense, that I don't be-
lieve in the existence of a supernatural being who influences natural
events.

Tax: Let's return to this shift from mindless to mind.

Huxley: It is a very important point. We only deduce the exist-
ence of mind in other persons from their behavior. I don't know what
you are experiencing; yet I have every reason for thinking that you
have a mind and subjective experiences. But it is only through your
behavior — what you say, how you gesticulate, and so on. When you
get back to the human ovum or early embryo, there is no indication
of any effective mindhke quality being present. And just as in the

AT RANDOM ■ 47

early stages of the individual human life there is no evidence of mind,
so in the evolution of life itself we see no evidences of anything one
might call mental properties in organisms less highly organized than
insects, octopuses, or fish.

Darwin: And I should think the ecclesiastics would not accept

these as having minds.

Tax: Minds, perhaps, but not souls.

Shapley: Yes, they would; some of them would. I have invitations
now to talk at five different theological seminaries — to the faculties,
not to the students, whom they still protect. One is Methodist, and one
Presbyterian, and one Unitarian, and one is— I don't quite know what
it is. They want to know what science is saying. And when I get there,
they don't say: "We have to draw a line between certain forebears
of man, and say, here is where mind came in; and there, soul; and
there, spirit." They don't expect that. Where are you going to draw
the line, Julian? Does an amoeba have a mind? It chooses between
food and non-food.

Huxley: That is not choice; we don't know that it chooses, m the
proper sense of deciding between alternatives.
Shapley: Well, it gets one and not the other.
Huxley: That is another matter.

Darwin: I should like to bring up another point. We are makmg
calculating machines that are already pretty good at doing the sums
we set them. But some persons have been trying to make machmes
that will learn. A very bright man I once knew wrote an interestmg
paper about this. He said that if you wish to teach a machine anything,
you must have a system of rewards and punishments. If it is a good
machine, it is going to be rewarded; and a bad machine is going to
be told "Don't do that!" Every time it gives the response you want,
it will be more habituated to it; if it gives what you don't want, it will
be less habituated. I think that in time— and not so many years hence
—we shaU have machines that won't need this elaborate complete
drill. The time will come when that machine will proceed to take
charge and tell us many things we don't know. As I see it, at some
time that machine will get up and say: "I am the first creature that

has a mind."

Huxley: I don't think you can speak of a mind without subjective

experience.

Darwin: But it will say it has subjective experience.

Huxley: I doubt it! So far as we know, subjective experience exists
only when there is a particular arrangement of sense organs, and these
very odd cells called neurons —

Darwin: Wait a minute. You're talking about the human bram,

48 • ISSUES IN EVOLUTION

which has I don't know how many million cells. The most elaborate ij
machine so far has only about 10,000 cells. By the time we get thisi
number up to a million, won't such a machine be able to do all these ;
things?

Huxley: How can it have a subjective experience? It's made of
metal instead of protoplasm.

Darwin: Why shouldn't metal have just as good a subjective ex-
perience as carbon hydrides? This same man I mentioned was asked
by a journalist, "Could your machine write a poem?" He thought a
minute and replied, "Yes, it could write a poem; but I think the kind
of poem it could write would be more enjoyed by other machines than
by a human being."

Huxley: I should like to stress this fundamental point: the real
nub of evolution, the aspect which is still the most mysterious, is the
fact of subjective experience, which is assuming increasing importance.

Tax: You are much less of a materialist and an atheist than Sir
Charles, yet you are the one who was proclaiming his atheism earlier.

Huxley: This has nothing to do with atheism.

Tax: If something is unknown and mysterious, it is very easy for
people to say it is supernatural — it cannot be explained naturally.

Huxley: That is not logical. 1

Darwin : I was accusing you of being a solipsist.

Huxley: Certainly not! But the point Tax raises is very important,
and it comes back to Shapley's earlier statement. At present, the fun-
damental barrier between most theologians and most scientists is that
scientists see no evidence of a supernatural agency interfering with
the course of nature, or any need to postulate one.

Shapley: This morning I was talking about religion in an age of
science. This religion would suit you very nicely, Julian, because it
gets away from superstition and miracles. Science can strengthen reli-
gion, and not upset it. There is no need of that. I've learned from
anthropologists that every primitive tribe, without exception, has a
religion. They thought one group up the Orinoco was without religion,
but that has been checked, and it was a misunderstanding. So religious
belief is built into us as part of a reaction against mysteries we can't
solve easily. To make ourselves comfortable, we turn to miracles and
the supernatural.

Huxley: Religion need not deal only with mysteries.

Shapley: No; it can be an ethical system.

Huxley: It can't be only that. I believe that the only way to define
religion in general terms is as an organ of man that deals with prob-
lems of human destiny and with things and events that are felt (here

AT RANDOM ■ 49

is subjective experience again) as in some way sacred. Religious ethical
systems always have these feelings of sacredness.

Kupcinet: What about the future of man and the population ex-
plosion?

Shapley: This morning I was talking on this general subject of
religion and science. I pointed out that the two most serious situations
facing us are, first, the hydrogen bomb and its control (either we live
with it peacefully, or we don't live at all) and, second, the population
explosion.

Stevenson: I'm glad to hear you say that, because last week I
wrote an article for the magazine Foreign Affairs, in which I said
that in my judgment the two most important problems in the world
were, first, nuclear weapons and, second, the disparity in living stand-
ards between the rich and poor nations.

Shapley: I don't know who stole the other's ideas, but we agreed,
didn't we?

Kupcinet: Governor, what did you say about the population ex-
plosion?

Stevenson: It is not for me to explain the population explosion.
It is, however, a political problem for this and other Western coun-
tries that, as population explodes, the rich nations are getting richer
and the poor are getting poorer. We must find some way of keeping
economic growth ahead of population growth. We must provide jobs
and employment, because masses of discontented, restless people will
turn to severe and authoritarian measures to further their economic
development. This problem seems to me equal in importance to that
of the existence of nuclear weapons.

Kupcinet: When you visited India recently, I imagine you found
a tremendous population problem.

Stevenson: Yes; but actually the Indian rate of population growth
is lower than ours. We always talk about how the growth rate of the
more fortunate peoples decUnes; but the United States has the largest
per capita income in the world, and yet our growth rate is now one
of the highest. I don't think this is necessarily bad. It depends on the
extent of natural resources and the degree of population density.

Shapley: Many areas in India are already highly overpopulated,
and their level of living is extremely low. On the whole, it is the coun-
tries that are getting poorer that are multiplying faster, and so the
disparity increases.

Stevenson: It has taken about forty to fifty years for any nation

50 ■ ISSUES IN EVOLUTION

to modernize or industrialize. That was true of the United States, of
Britain, Germany, and Japan, and it is true of the Soviet Union. At
that rate, India and China will be industrialized at the beginning of
the next century. Now the industrialization of populations of that
order of magnitude — over a billion people in China by the year 2000
— means that the distribution of power and authority in the world
is going to shift. The United States has taken for granted for quite
a while that we are the center of gravity in world affairs. Now we are
sharing this position with the Soviet Union. It will not be long before
these new, vast, and overmighty populations emerge industrialized,
and then we shall be only one of several centers of world power.

Huxley: At the Planned Parenthood International Conference in
New Delhi this spring, they were discussing a paper by two American
economists — Coale and Hoover — who had been called in to advise
India about industrialization. The points they made are somewhat
as follows: Industrialization does not happen by itself. A great deal
of capital investment is needed, as well as investment of energy and
skill and the like. But every million extra people means that some of
this capital and skill must go into feeding, housing, servicing, and
educating these. After going into the problem quantitatively and very
carefully, they emerged with this conclusion: unless India halves its
birth rate within about thirty-five years, she will never be able to in-
dustrialize. The Indians now realize that their first problem is popula-
tion control, not industrialization. They will not achieve industrializa-
tion unless they cut their population increase.

Darwin: I think that, in spite of his mind, man is still an animal,
and he will obey the rule that no matter how much food is produced,
there will be too many people asking for it. Suppose the United States
exported its excess of corn to India, let us say; what would be the re-
sult? The population of India would jump, and they would still be
hungry. We have to attack the other side of the problem of overpop-
ulation, and nobody knows how to do it.

Stevenson: The old corrective forces of war and pestilence have
now been done away with.

Darwin : Julian and I disagree a great deal about the way popula-
tion has been increasing in the past, but I think he will agree that
there has been a radical change in the last two hundred years — quite
a different order of increase. This multiplication began two hundred
years ago — or a century ago; I don't care which we say. I maintain
that this is because man has solved the problem of natural selection;
it does not operate on us any more. The number of people must be-
come constant, since it cannot go on increasing indefinitely. But what

AT RANDOM • 51

is going to limit it? Either there will be a reversion to the old system
of natural selection, or else we shall see this sort of problem: the man
down the street has not enough to eat; you have food, but enough for
only one person. Are you going to give it to him, and die yourself,
or are you going to keep it?

Stevenson: You don't think productivity will keep pace with in-
crease in population?

Darwin: It can't.

Huxley: I agree with Charles that this idea of a race between pro-
duction and population is the wrong way to look at the problem. We
shall eventually reach some sort of balance; the question is whether
it will be a regulated and tolerable balance or an extremely unpleasant
one. The only way to tackle the problem constructively is to reduce
the rate of reproduction.

Going back to one point, Charles, where I slightly disagree: you
said the high rate of multiplication began two hundred years ago. Cer-
tainly it did; but since then we have had the extraordinary phenomenon
of an accelerated increase. The rate of increase per annum never
reached one per cent until the present century; it is P/4 per cent al-
ready and still climbing. People just do not realize that when babies
born this year are old enough to vote, there will be one billion more
people for them to vote about: one billion more by the time they are
twenty-one. Absolutely appalling!

Stevenson: The population of the world is increasing at the rate
of 100,000 a day, is it not?

Huxley: Oh, much more now. When I first became interested in
this problem, I was shocked to find the rate of increase was 76,000
a day. When I had to write about it a few years later and looked into
the statistics again, it was 91,000. Now it is about 140,000. That is
the net gain every twenty-four hours.

Darv^in: Since we entered this room, six or seven thousand more
people have been bom.

Kupcinet: Well, our audience is increasing.

Stevenson: We'd better get out of here in a hurry!

Huxley: By the year 2000, the net increase will be half a billion
a year.

Shapley: It begins to look as if the human race is one of the worst
things that has happened to the earth.

Huxley: Either we are going to control the population explosion,
or we shall become the cancer of the whole planet. If we are not care-
ful, we shall be back with famine and starvation and all the rest of it,

Kupcinet: What are your suggestions for control?

52 • ISSUES IN EVOLUTION

Huxley: First, we need a cheap, simple, oral contraceptive, and
then we have to persuade people to take it. In Japan, for instance,
they did not have to be forced to use contraception; in fact, they were
quite easily persuaded to practice abortion. You can have various
degrees of persuasion — economic influence, for instance. Already in
India, in Madras State, they pay men fifteen rupees each time they
are sterilized — well, I shouldn't say "each time," since you can have
it done only once! Of course, this is under certain safeguards, and they
must have had four children already.

Darwin: But we have to face the appalling difficulties involved.
If the Chinese, or any other people, are really ready to tolerate a lower
standard of living than we are and if both know how to control our
populations (which we don't yet), what is the consequence? In a hun-
dred years there will be three times as many Chinese as now. Any
group that believes in not limiting its population automatically scores.

Huxley: We shall have to establish an international, global poUcy.

Darwin: Under whose control?

Huxley: Some central organization; not the United Nations in
its present form, because it has no mechanism for dealing practically
with the population problem.

Darwin: World government is the obvious answer. But now sup-
posing a world government limits population, but one part of the world
says: We don't like your limitations. We are going to have more chil-
dren because we are more important than anyone else, and you can't
have too many pigmies in Central Africa — or whatever race it may
be. What is the world government going to do — kill them?

Huxley: That is a highly hypothetical situation.

Stevenson: You said that unless societies Hke China and India
arrest their population growth, their prospects for industrialization
are limited. Do I conclude that you would not make an all-out effort
to improve their economic growth now?

Darwin: If you put all your effort into this, you would be fighting
what is definitely guaranteed to be a losing battle.

Stevenson: I think two subjects have become a little confused
here. I was saying a moment ago that to me the two most important
facts in the world today are, on the one hand, the existence of nuclear
weapons and, on the other hand, the disparity of living standards
among nations; that we shall have to control the nuclear weapons
and eliminate them before they eliminate us; and that we must im-
prove the standard of living in those countries that are getting poorer
while we are growing richer. Otherwise the pohtical Situation will
be more unstable, and the consequences are inevitable. Then these
gentlemen said that the real problem, of course, is the bursting pop-

AT RANDOM • 53

ulation, which is what Dr. Shapley had said. Well, we shall have to
deal with them both. But we certainly can't suspend our efforts to im-
prove the economic lot of the underdeveloped countries while we wait
for them to arrest their exploding populations.

Huxley: Governor Stevenson says we must aid other countries to
raise their standards of living; I entirely agree. But the key word here
is aid. Eventually we shall have to combine all the different forms of
aid — bilateral, multilateral, and international — and link these up with
population control. Coale and Hoover, for instance, make it quite
clear that if India's population goes on increasing as fast as it is now,
all the money being poured into India, far from helping her to in-
dustrialize, it will lead to a point of no return, with fewer jobs and
more people living at lower standards. We must evaluate population
problems and tie in the remedies with aid. One of the conditions of
aid would be that they should have a program, as India and Japan
and a few other countries have, of trying to reduce the rapidity of in-
crease. I think this is perfectly legitimate. If a country asks for finan-
cial or technical aid and investigation shows that the rate of popula-
tion growth is so great that all the aid will go down the drain unless
the growth is checked, then I think there is every right to say: "You
won't get aid unless you put some of it into trying to check your rate
of increase." That, I think, is what will happen within twenty-five
years.

Stevenson: You would make reducing the rapidity of increase a
condition of giving them aid?

Huxley: Some of the aid would be given them in the form of tech-
nical assistance, free contraceptives, or expert advice. I don't think
that is compulsion.

Darwin: I wish I could hear an economist discuss this endless talk-
ing of industrialization of all these other countries. By the time we
have done it, won't we be reduced to starvation ourselves, because
half our life depends on export?

Stevenson: As the world's economy has improved, the economy
of every nation is improving, too. The best markets are always the
most highly industrialized and most highly developed areas.

Kupcinet: We have been talking about the underdeveloped coun-
tries. What about the United States and England? Are we faced with
any serious population problems?

Huxley: We are faced with the problem of pressure on mere space
in Britain. We live on a small island, much of which is uninhabitable
and unsuited for agriculture. Communications, house-building, in-
dustrial developments, national parks, recreation, and military estab-
lishments are all competing for space and the results are becoming

54 • ISSUES IN EVOLUTION

increasingly alarming. We established national parks only ten years «j
ago, and now already three of them have been invaded by industry
or atomic energy plants.

Kupcinet: Perhaps we should move to some other planet.

Shapley: Mars is no good, and Venus is probably no good. And I
planets around other stars are too far away, so I don't think there is
any solution to the population problem through astronomical migra-
tion.

Huxley: Even if Mars were inhabitable, think of shipping off
140,000 people every twenty-four hours, non-return!

Kupcinet: Governor, you made a very important point before,
which we rather glossed over. You pointed out that overpopulation
can lead to authoritarianism — a communistic or some other kind of
totalitarian state — when people are looking for a quick answer to the
problem.

Stevenson: I think that it is now happily becoming generally ac-
cepted in the West and in this country — I myself have talked about
it for a long time — that this is really a great danger to our country.
A fact of greater importance to the Western democracies than the mili-
tary might of the Soviet Union has been, as I see it, the desire for
economic development of the emerging countries. These nations, one
by one, are going to try desperately to improve their standards of liv-
ing. They have reached the conclusion that disease, misery, and pov-
erty are not the immutable destiny of man; they, too, can share the
good things of this extraordinary century. So they are going to evolve
and develop economically one way or another. We must offer them
an alternative to the Communist method of forced labor, forced sav-
ings, and economic development, which has great appeal for them
because they have the example of the speed with which the Com-
munist states have developed in these last forty years — for example,
the Soviet Union — whereas our societies are older and we also bear
the burden of colonialism. We have handicaps. Therefore, we must
get at this task in concert with our friends and co-ordinate our plans
to make the maximum use of the resources we have; and we have
enormous resources to bring to bear on this problem of economic
development. But this does not answer the population problem; in
fact, it may aggravate it.

Darwin: I should like your opinion as an experienced political
figure. It seems to me that by the time your country has twice its pres-
ent population, the degree of liberty must be lower. You must have
more laws to control twice as many people.

Stevenson: I suppose that is inevitable.

Darwin: And isn't that really the point of what you are saying
about the communistic systems? I fear — and it is a very great fear

AT RANDOM • 55

that this country will gradually lose its liberties as its population in-
creases, like all other countries.

Stevenson: If you say that as population multiplies, the complex-
ity of society increases and therefore the number of rules needed to
regulate modern society, I think that is true. But I do not think that
this in necessarily a fatal impairment of liberty in the sense of the in-
dividual's right to participate in the choice of his government, which
is basic.

Huxley: That is only one kind of liberty; there is the liberty to
park your car, for instance, and the liberty to buy what you fancy.
As things get really tight, you will have to curtail that liberty and have
rationing again.

Darwin: I see no escape from it myself. If I may go back about
three hundred years, to what I consider the normal condition of man-
kind when natural selection was, on the whole, holding population
nearly constant, in the literature of those times — in Chaucer or Shake-
speare, for instance — there is just as much cheerfulness, or even more,
than there is now. I beUeve people in the future will be just as happy,
but their happiness will be felt when they feel a Uttle bit safer — some-
thing that we take for granted. People in the future would love to
have lived now; they will think how happy we must have been.

Stevenson: My impression is that the Black Plague swept London
in the sixteenth century, just over three hundred years ago. I don't
believe we want that again.

Darwin: No, we don't. But I should think people at that time were
made happy by much slighter things than we are now; and I believe
that happiness is quite a separate thing from prosperity.

Stevenson: I had not attempted to equate happiness and prosper-
ity; on the contrary, this would be a contradiction of most Christian
teaching.

Huxley: But isn't that a commonplace of much business thought
in this country?

Stevenson: Yes, unhappily. That is one of our limitations. We are
all famiUar with day-to-day reporting in the press and the emphasis
it puts on the very things we have been talking about here: the com-
placency in this country, the euphoria, the sense of satisfaction, the
preoccupation with getting rather than giving; the idea of "two Cadil-
lacs in every pot and two chickens in every garage." We have a long
way to go to restore a sense of purpose consistent with our own tradi-
tions and ideals and also with the realities of the world in which we
live. We have lived a great deal of mythology, for a long time.

Kupcinet: You blame our communications: press, radio, tele-
vision?

Stevenson: They have contributed to it. They have a great re-

56 ' ISSUES IN EVOLUTION

sponsibility for correcting all the unrealities in which we live — the
mythology, from which I am afraid we have suffered, about the true
plight of the world, the very sort of thing we have been talking about
here; about the position of this country and the steps it must take to
regain its position.

Kupcinet: You think our country might be declining, after our
star has been in the ascendancy for a long time.

Stevenson: The center of gravity in the world has been moving
from east to west for a long time. In this century, it suddenly jumped
over the Atlantic to this country. Now it is suddenly arrested, and
two centers of gravity emerge, Washington and Moscow or, if you
prefer, this country and Russia. But I think our day at the center of
the stage is going to be brief and that new centers are going to emerge,
largely in Asia. I don't know whether countries like China and India
will be able to modernize and become centers of power, if population
outruns economic growth. But certainly the early assumption that the
United States is going to be the dominant influence in the world is
something we have to re-examine pretty carefully.

Darwin: Just like the British in the mid-nineteenth century.

Huxley: Which we now know wasn't so.

Stevenson: I don't think there is going to be any "American Cen-
tury"; I think more humility is perhaps indicated for this country.

Huxley: Humility and a global sense. In the long run, we shall
not really get anywhere unless we replace the idea that happiness
comes from increased quantity of things — two television sets, for in-
stance — with the idea that it comes from increase in living, however
you define that.

Tax: But in much of the world, happiness is correlated, not with
material things, but in some degree with having enough to eat; and
most people do not have that. A very small part of the world has a
problem of too many things.

Huxley: But I am talking of the long run. Governor Stevenson
said we have to compete with the Soviet Union; we have to compete
not only in various economic matters but also in giving a goal, an
aim, for living.

Stevenson: All the reasons why Moscow is a dull city and New
York is exciting and interesting.

Huxley: The official Russian doctrine, which they are often able
to put across, is that in the inevitability of history the whole world
is going to go socialist; but the West has no comparable vision of the
future.

Stevenson: We must recapture a similar sense of purpose, and we
must dedicate ourselves with the same determination as the Russians.

AT RANDOM • 57

Huxley: But not to the same goal.

Stevenson: To the objectives that are purposeful for us.

Darwin: I should have thought you would say liberty is our goal.

Stevenson: I was going to say that the Communist system is the
antithesis of what most of those peoples who are now emerging from
long oppression into independence want.

Huxley: But so long as they do not have enough to eat, they won't
mind about liberty.

Stevenson: Certainly.

Huxley: Liberty, again, is only the foundation; it is freedom to
do certain things.

Darwin: An old friend of mine once said liberty is the privilege
to be selfish.

Shapley: The discussion here is very anthropocentric. All this
time we have been talking in terms of man about man. To be sure,
he is in a mess, and it is a problem for us. But think what a mighty
universe this is and what a small part man plays in the whole.

We should remember that in this city a few years ago Harold Urey
and Stanley Miller carried out an experiment that assures us of what
we had rather suspected for a long time: that one can bridge the gap
between the inanimate and the animate and that the appearance of life
is essentially an automatic biochemical development that comes along
naturally when physical conditions are right. And physics is about the
same throughout the universe we know; certainly chemistry is; we can
test that. And when physics and chemistry and the climate are right,
I think the appearance of life is inevitable.

But now what would it evolve into? I think we fool ourselves in
thinking that we are important in the universe. Our sense organs are
not so good as those of a good many other animals here on earth. We
have a pretty good mind, a pretty good forebrain. But on all these
millions and probably millions of millions of suitable planets with
the right chemistry, climatology, and all, there must have been other
experiments with life. Our sun is an average star, off at the edge of
one galaxy. Why should you expect that the only place where there
can be high nervous reactions is on this planet, on number three,
circling a run-of-the-mill star?

I do not believe that man is duplicated anywhere, for there are a
million variations on the animal theme on this planet. But there is no
reason to think that there have not been highly sentient developments
on other planets. They have had the same length of time, the same
sort of experience, some of them; so I think we are a little vain or
anthropocentric if we consider ourselves the center of life and the
highest beings in the universe.

58 • ISSUES IN EVOLUTION

Coming back to one of your earlier themes, I think we have to ad-
mit that the price of social organization is a loss of certain freedoms.
The more our society develops, the more some of our liberties will
be questioned. We won't let you park your car in the wrong zone, for
instance. But I think we are happy to give up some of our liberties
for the privilege of being civilized.

Huxley: I don't see much consolation in thinking that there are
highly sentient beings elsewhere in the universe, when we are in a
mess.

Shapley: But why seek consolation, Julian?

Huxley: Wasn't that what you were doing?

Shapley: Let's seek adjustment.

Huxley: It is very nice to think they are there, but what have they
to do with us? They do not help us out of our present mess.

Kupcinet: Would you mind giving your ideas about the existence
of life in the universe in more detail. Dr. Shapley?

Shapley: Life, of course, is a natural thing. We can evolve it, and
during the coming week we shall hear about evolving it in test tubes.
What I should like to emphasize is that there are so very many chances
throughout the universe for the conditions leading to life. Within a few
hundred light-years of earth there are at least 20,000 stars just like
our sun. They have been through the same experience. To deny them
this high privilege of having philosophers talking about the universe
is not fair.

Huxley: Unfair to stars?

Kupcinet: But what form of life would you say exists there? You
said that there probably would not be man.

Shapley: Well, high sentient beings. This so-called mental dis-
ease, this neurotic complex we call "intelligence," is a pretty common
quahty. It is not confined to man but goes down through the whole
animal world. But the point I want to make is this: There are at least
10^° stars within the distance we can reach with our telescopes. That
means one hundred thousand million billion stars. At one time, in
the past, matter was crowded together, and there was a chance for
a great many collisions and planet-forming operations. I do not see
why we, who live out on the edge of this galaxy, should think our
planet the only blessed place. Now that certainly is relevant to phi-
losophy, and it does and can bear on religion. That is why, when I
go around to the colleges, I am always asked to talk about religion
in an age of science. And the response I get is very moving. You see,
there was a time when we might say we swore by a one-planet god,
or deity, or something of that kind. That's over! We have to reaUze
that this is an enormous universe, and it should be a pleasure to be

AT RANDOM • 59

in such a big operation. Fancy the myopic predictions and concepts
of the ancient Church Fathers compared with what we can get now
from the laboratories or from the philosophers who are following
them.

Huxley: The population experts are not very hopeful.

Shapley: Again you are being anthropocentric.

Huxley: I should hope so! After all, we are anthropos.

Stevenson: Really, the greatest problem we have to face is the
fact that, for the first time in all human history, we have split the atom
and released forces of nature that have not heretofore existed. We
have, in a sense, become master of the elements, while at the same time
we have been unable to master ourselves. That is how far science has
outrun politics. Our major failure is our inability to keep pace with
the ordering of man's affairs, with his intellectual triumphs. Isn't pop-
ulation just one aspect of this?

Huxley: You can look at it in an even more general way. Physics,
which is, after all, the most mathematical of the sciences, is also the
simplest. Chemistry is more complicated; biology still more so, but
we are making progress. Psychology and sociology are still worse. But
there has been enormous progress made in this hundred years of
biology. They are now showing what the first beginning of life was
hke, and I am sure that we shall create life in the test tube before the
century is out. And, after all, Charles, your grandfather was the first
person to start a comparative science of psychology, with his great
book on The Expression of the Emotions in Man and Animals; and
then the Freudians and the ethologists took it a little further. We are
beginning to know something about it, but we are still very young.
This is what we forget: man is just at the beginning of his evolutionary
career.

Shapley: And why are we so far along in our scientific career?

Huxley: Physics is easier than biology, and biology is easier —
less complicated — than human affairs.

Darwin: But it does come back to the question. Can we master
ourselves? That is the central problem.

Huxley: In the long run, as Muller said, we have to master our
own genetics.

Kupcinet: What about Muller's theory of freezing the reproduc-
tive cells of persons of superintellect and implanting them by artificial
insemination at a later date?

Huxley: That is not his theory, only his suggested method.

Kupcinet: Can it be done?

Huxley: It is being done with animals, of course; and if it can be
done with animals, it can be used with man.

60 • ISSUES IN EVOLUTION

Kupcinet: But is it practical?

Stevenson: I'm not going to run for any office on that platform.

Darwin: I should put it this way: Do you see yourself as really
happy when you know that your wife has had a child by Isaac New-
ton?

Huxley: I can imagine some persons being quite proud.

Kupcinet: Didn't Plato recommend a similar thing?

Darwin: He did, rather, didn't he?

Huxley: It is practical. Muller's central point, though, is that if
we don't do something about controlling our genetic inheritance, we
are going to degenerate. Without selection, bad mutations inevitably
tend to accumulate; in the long run, perhaps 5,000 to 10,000 years
from now, we shall certainly have to do something about it.

Stevenson: Is it certain that as the quantity of people increases,
their quality necessarily decreases?

Huxley: Oh, no. The point is that, in earlier centuries, natural
selection wiped out bad mutations. A man with a very serious eye
defect — or whatever it might be — simply would not live to maturity.
But we correct these conditions with spectacles and other artificial
aids. For instance, we keep alive people with hemophilia who would
undoubtedly have died otherwise. Most mutations are deleterious,
but now we keep many of them going that would otherwise have died
out. If this continues indefinitely — and that is the whole point of Dar-
win and his revolution in thought, that time is of the essence in evo-
lution — then the whole genetic capacity of man will be much weak-
ened.

Darwin: Muller's plan impHes that the masters of the world will
be Muller and his fellow geneticists, whereas I know, and you know,
that it will have to be the politicians. Can we educate politicians?

Stevenson: Now you are asking too much.

Kupcinet: We have running around the country a whole flock
of presidential candidates who say that they are not candidates; nat-
urally, everybody knows they are. There is a measure of deceit—

Stevenson: — and strategy —

Kupcinet: — in this, which I think we ought to attack someday.
But what advice would you give them. Governor, if you were asked?

Stevenson: I should advise them to sit down with some of the
world's greatest scientists, like this, and they will realize how impor-
tant science is.

Shapley: Or maybe they will become so pessimistic about it all
that they will just withdraw from poHtics.

Stevenson: I must say that, after talking here this afternoon, I
was never quite so content to be growing older.

AT RANDOM • 61

Kupcinet: Well, Governor, you set a new record in speaking sense
to the public. I suppose you go along with the theory that all political
candidates should talk sense; is that possible?

Stevenson: It will be possible only when the kings are philosophers
and the philosophers are kings. That is a long way off. Certainly it
should be the ambition of our politicians and the standard that we
demand from them; but, until we do so, I do not think we are going to
get much better politicians.

Darwin: What is the definition of sense? I should think the fun-
damental definition of sense is agreeing with me.

Huxley: Or with the facts of nature?

Kupcinet: Governor Stevenson has to leave now for another en-
gagement; but, before he goes, I should hke to ask him this question:
Thanksgiving Day is just around the corner; and what are some of
the things we have to be thankful for?

Stevenson: I have a great deal to be thankful for: my health, my
children, my grandchildren, my friends. And I suppose that as a na-
tion we can be thankful that we are alive. Perhaps this is the most
formidable problem we shall have to contend with for a long time yet.
It reminds me of a remark I heard the other day: A little girl, asked
by her aunt, "What do you want to be when you grow up, dear?"
replied, "Alive."

Shapley: And you are thankful you have work to do.

Darwin: And that you are contributing to the population problem
— you referred to your grandchildren.

Kupcinet: And isn't it every man's ambition to leave the world
a little better than he found it? Whether we do so, of course, is prob-
lematical.

Shapley: It should be better; that is in the evolutionary picture —
improving conditions, advancing to further development, subscribing
to the growth motif in the whole universe.

« « *

Kupcinet: Professor Tax is largely responsible for assembling all
these noteworthy people here for the Darwin Centennial. How did
you get the idea, and how did you put this thing into operation?

Tax: About four years ago I happened to be in New York at a
conference where they were discussing evolution and physical anthro-
pology; and the date of the Origin of Species came up. I thought, some-
body should celebrate the centennial of the Origin. I came back to
the University of Chicago and discussed this with the Chancellor and

I

62 • ISSVES IN EVOLUTION

various other people, who thought it might be a good idea. But they
suggested that we should be cautious, since we had no way of know-
ing that there would not be other centennials around the world. I did
the wise thing and wrote to Sir Charles Darwin and Sir Julian Huxley,
asking if they would come to a centennial celebration at the University
of Chicago in 1959. I thought their answer might very well be that
they would be tied up celebrating the centennial in England. Instead,
they wrote that they would be glad to come; so we saw that nobody
else had preceded us in thinking about this and that we were not step-
ping on anyone's toes.

Huxley: There was a centennial celebration in England in 1958
— the centennial of the Darwin-Wallace paper at the Linnaean So-
ciety, in which the idea of evolution by natural selection was first
made public.

Tax: From that time, we have been working for four years. We
had a committee to choose a theme and select participants, and we
finally decided that we should try to find out what is now known,
after one hundred years, in various fields of knowledge that impinge on
evolution or have been influenced by Darwinian theory. So we brought
together scientists all the way from astronomy to biology and anthro-
pology and psychiatry to talk about the evolution of "life itself, the
origin and evolution of life, and the evolution of man and the mind
— themes that in some degree were in Darwin's mind one hundred
years ago.

Huxley: I was very much honored to receive an invitation to come
here for three months with the title of Visiting Professor — but really
professing nothing, except helping so far as I can with the business
of this Centennial. I am sure that it is going to be very important.
To me its most interesting feature is that a great many persons con-
cerned with the sciences of man — anthropology, archeology, psychol-
ogy — are going to discuss problems with persons concerned with the
biological, and some indeed with the physical and astronomical, sci-
ences. There has been too much cleavage between anthropolocrists

in the broad sense — and biologists. This Celebration should b^ very
fruitful in bridging this gap.

Darwin: I learned a very interesting thing at the Linnaean celebra-
tion last year. The joint paper by my grandfather and Wallace was
printed by the Linnaean Society in July of 1858. Only two notices
were taken of it. One was by the president of the Society, who at
Christmas reviewed the activities of the past year; and he said that
they had had a grand year with a great deal of success, but unmarked
by any conspicuous events whatsoever. And the other, I think, was a
professor at Dublin, who wrote a short paper saying that half the

AT RANDOM 63

things Darwin and Wallace said were familiar and the other half

wrong.

Huxley: The theory of evolution was in the air, however. Asa Gray
had got halfway; Lyell, a third of the way. It would have been formu-
lated well before the end of the century, even if Darwin had died.
But it would not have happened in the same decisive way. Darwin
not only had this brilliant inspiration of natural selection but also
collected a great volume of facts to buttress the idea of transforma-
tion — which was what evolution was then generally called. And he
did what Wallace did not even try to do until much later: he deduced
many consequences from the principle of natural selection, which you
can still read with profit today. For instance, it is amazing to find in
the Origin the idea of what we call biological advance or improvement
in organization and the idea of branching, or divergence, both of them
well documented and clearly explained.

It is very interesting that Darwin was so hesitant to pubUsh his
theory for all sorts of psychological and scientific reasons. Actually,
I think it was a good thing he timed it as he did; if he had delayed
much longer, it might have become stale, and if he had put it out
quickly, as Wallace put out his material, it would have been prema-
ture and would not have come out in such a convincing way, and we
today would not have been anywhere near so far advanced. Look
what Darwin did with the whole idea of sexual selection and variation
under domestication.

Darwin: But the majority of the scientists took twenty years after
the book appeared before they accepted evolution. Julian's grandfather
accepted it at once, but a great many people did not.

Huxley: Yes, of course; but the people who mattered did accept

it immediately.

Darwin: I have an enormous admiration for Julian's grandfather.
I remember once he was defending the evolutionary theory against
a man who was a good scientist but insisted that a species was a species.
And Huxley took what I regard as the absolutely perfect example. He
said, "Do you really believe that at one moment all the molecules
jump together suddenly somewhere in space to create a perfect full-
grown rhinoceros?" I think his choice of rhinoceros was perfect; an
elephant would not have been nearly as good.

Tax: I think it is important to say — as some things Sir Julian has
said imply— that the Origin of Species and all of Darwin's works are
not being celebrated as something in the past. They are books that
still need to be studied, in spite of one hundred years. You cannot
say that about many scientific books.

Huxley: Not all Darwin's books can still be studied with profit,

I

64 • ISSUES IN EVOLUTION

of course. Animals and Plants under Domestication, for instance, is
useful only for historical reasons; but the Expression of the Emotions
and the Origin and much of the Descent of Man are still very well
worth reading.

« * *

Kupcinet: Before we conclude this program, what hope do you
see for mankind? Are we going to regress or progress?

Huxley: The three big problems are preventing our civilization's
being wiped out by atomic warfare; preventing overpopulation from
engulfing the world; and bringing the underprivileged nations up to
an improved standard of living. I think that, if we really try, we can
deal with all of these reasonably well. Of course, we shall never suc-
ceed 100 per cent; evolution never does. All the results of evolution
are compromises.

Shapley: You sound like an optimist.

Huxley: Well, I am; though I'm a tempered optimist. Charles is
the pessimist.

Darwin: I am afraid my outlook is that we have to let the future
happen.

Huxley: But can we do nothing to alter it?

Darwin: I do not think man will master himself, nor do I think
we shall develop a world government. There not being enough to eat
is what worries me.

Kupcinet: It boils down in your estimation to enough to eat?

Darwin: Finally, yes. Don't you think so?

Kupcinet: I agree with you, but I am a little more hopeful that
we can master such a basic problem.

Darwin: I contend that whenever we have more to eat, we shall
have too many people asking for it. Remember, half the world does
not have enough to eat now.

Huxley: So we must reduce the number of people.

Kupcinet: Do you see any hopeful signs that birth control will
eventually take hold?

Huxley: In the last few weeks, two official groups — the Draper
Committee and the Senate Foreign Relations Committee — have re-
ported that the United States should take population increase into con-
sideration when granting foreign aid. Even Life magazine came out
with a spread on birth control in a recent issue, and two major net-
works have had programs about overpopulation. All this happened
in six weeks.

Darwin: Most encouraging.

Kupcinet: What about the worlds outside this planet?

AT RANDOM • 65

Shapley: They will get along all right. Even eliminating this planet
is not going to affect other planets in this system appreciably, and cer-
tainly not the rest of the universe. But the earth will go on, as it has for
the several thousand million years before man began messing up this
particular planetary surface. And man will not escape this surface;
he may pepper the moon, here and there, with rockets, but he can do
nothing serious.

Darv^in : I don't think we should ever say with real confidence that
we could not throw the solar system into a new star — a supernova.

Shapley: Even a supernova popping up here would die off soon.

Darwin: We don't know enough yet, but —

Shapley: But if we try, we may learn how to blow up the whole
earth.

Darwin: That would solve our population problem.

Shapley: Seriously, it seems to me that our problem is to try to
be rational; to use reason —

Huxley: — and a little imagination.

Shapley: It will take imagination and opportunity and freedom
from too much fussing around with diplomacy. Man's worst enemy
is man; that has been recognized for a long time. So if you get rid
of man, man will have no enemies. One of the best things to be said
for this planet is that it is a wonderful place on which to set up lab-
oratories and mount telescopes to study the rest of the universe.

Huxley: Make the world safe for astronomy!

i

SOL TAX

INTRODUCTION TO
THE PANEL DISCUSSIONS

This evening I shall inaugurate the Centennial Celebration as a whole.
Now I introduce only the series of panel discussions on issues in evo-
lution, which is the heart of the Darwin Celebration.

Charles Darwin's book, Origin of Species, published one hundred
years ago today, did two different things. First, it presented the rich
wealth of empirical evidence needed to convince reasonable men that
the variety of forms of plant and animal life, including man, owed
their similarities and differences to natural causes; all of living nature
is part of an ongoing process of evolution. Second, the book presented
particular theories of the mechanisms through which evolution oper-
ates, particularly the mechanism of natural selection, or the survival
of the fittest. Note, indeed, that the full title was On the Origin of
Species by Means of Natural Selection. The book would not have been
convincing without both.

If God did not in six days, six thousand years ago, create the dif-
ferent species we see about us, how did this wonderful variety come
about? If all plants and animals, including man, are part of a single
system, how did they arise one from another — difference out of same-
ness? Roses beget roses; termites beget termites; men beget men. Com-
mon sense sees this continuity, yet denies the relationship. It requires
great imagination, as well as logic and evidence, to see that roses,
termites, and men are cousins. It requires a change in habits of thought
from seeing things as fixed and static to seeing things as always chang-
ing. Europe in the mid-nineteenth century was doubtless ready for a
revolution in human thought. Darwin's book provided at once the
call to arms and a full arsenal to bring it off— an arsenal of concepts
and of facts impossible to explain away.

This week at the University of Chicago we are not examining the
notion of evolution itself, which all of us now take for granted as much
as we do the fact that the earth is a sphere revolving around the sun.
We are looking at the particulars. After one hundred years of Dar-
winian theory, where do we stand?

Each of forty-five specialists has, in the past three years, reviewed

67

68 ' ISSUES IN EVOLUTION

his special knowledge and reconsidered it from this point of view. We
have exchanged our papers, read, learned, criticized, and revised.
Meanwhile, our committee in Chicago was reading the papers. Almost
a year ago it became empirically evident that we could deal with
questions of evolution under five headings: "The Origin of Life," "The
Evolution of Life," "Man as an Organism," "The Evolution of Mind,"
and "Social and Cultural Evolution." By correspondence, the issues
so classified began to take form. This autumn at the University of
Chicago some thirty faculty members and fifty selected graduate stu-
dents from twenty different departments volunteered to study the
papers and to think and talk through the issues in the study of evolu-
tion, as seen under these five headings. By the time we all gathered on
Sunday, November 22, we had working documents at hand, and it
was possible to agree on the agenda for discussion. All told, there are
some fifty major questions for discussion, which in the coming five days
will fill in our picture.

Charles Darwin broke through a tremendous fog and, one hun-
dred years ago this very day, gave us a new understanding and per-
spective, on the basis of which we have done a hundred years of fruit-
ful research. The tremendous knowledge gained in these hundred
years of science we hope this week to summarize and synthesize. But
more than that, I at least have some hope, or fond illusion, that on
this occasion and in this hall we can take a new, great step forward,
to begin a second century of understanding ourselves and our cosmos
that will do justice to our heritage and give hope for our future.

Without further ado, I think we should turn to the first of these
panel discussions and give our fellow scientists every opportunity for
discussion of the first topic, "The Origin of Life."

PANEL ONE
THE ORIGIN OF LIFE

Chairmen: Harlow Shapley and Hans Gaffron

Panelists: Sir Charles Darwin; Theodosius Dobzhansky; Earl A.

Evans, Jr.; G. F. Gause; Ralph W. Gerard; Hermann J.

Muller; C. Ladd Prosser

Topics for Discussion

1. The scientist's approach to the question of the origin of life is not
in need of an exhaustive definition of what life is. We must attack
from the naturalistic point of view, namely, that principles un-
known or unknowable to science cannot be used to solve the prob-
lem. In other words, we proceed under the assumption that life is
a process that escapes at present our complete understanding only
for reasons of its complexity.

2. Darwinian evolution is now considered a fact and is the basis of
modern biology. On the other hand, any answer to the question of
what happened before Darwinian evolution began is largely specu-
lation. No existing and recognized forms of life are primitive
enough to be considered related to any primordial organism or the
first living cell. The viruses, which are not cells but are apparently
related to the most important constituents of living cells, namely,
the genes, exhibit attributes of living things only as long as they
interact with the structure of a living cell.

3. The now dominant idea that living things originated from non-
living matter is a consequence of our knowledge of the earlier and
later phases of the natural history of the earth — the former as con-
cerned with cosmological inorganic evolution, and the latter with
what happened, once life had appeared on earth. The assumption
that life originated from non-living matter must be made by the
modern scientist if he believes that the question "What is life?" be-
longs in the natural sciences at all.

4. Therefore, the origin of life presupposes, first of all, the natural ac-

69

70 ■ ISSUES IN EVOLUTION

cumulation of suitable raw materials. Astronomy and chemical ge-
ology provide methods for solving this question. Further presup-
posed is a gradual evolution of increasingly complex organic sys-
tems from the raw materials until a self-contained unit appears
which we would be willing to recognize as a living thing. To attack
this problem from the side of living things, microbiology, biochem-
istry, and genetics provide the tools.

5. Proceeding from this basis, we may subdivide the problem into
technical questions that are amenable to straightforward scientific
research. For instance:

A. Did the early conditions on earth favor the accumulation of
organic substances? What were these conditions?

B. Were the first organic compounds of such kind that they could
be readily transformed into parts of living things?

C. At what stage in this development could one assume a com-
plexity that guaranteed self-replication?

D. What principles govern self-replicating macromolecules?

E. How does the structure of nucleic acid specify biological prop-
erties?

F. Are enzymes needed for the production of nucleic acids, which
are, in turn, needed for the production of the enzymes?

G. Modern life on earth is extremely uniform in its basic metabolic
reactions. How is this to be explained? Is it to be interpreted
as a unique (highly improbable) event, or the result of numer-
ous chance combinations followed by selection?

H. Can life originate under present conditions on earth?

I. What were the energy sources allowing for a continuous increase
in complexity of pre-biological organic systems?

J. When and how did the change from anaerobic to aerobic con-
ditions occur?

6. What is the probability of life on other planets?

7. What are the possibilities of transport of germs through space?

The Discussion

Shapley: The Committee, the origin of which is, I suppose, a late
phenomenon in the course of evolution, has properly noted that an
examination of origin should precede examination of evolution and
has assigned us the subject of the origin of life. Once we have taken
care of that phenomenon and are convinced that fife actually has
originated and after we have discussed a bit that interesting activity,
other panels will take care of, first, the evolution of life; second, man

PANEL ONE: THE ORIGIN OF LIFE • 71

as an organism; third, the evolution of mind; and, finally, social and
cultural evolution.

Shapley: Let us begin by reading the first item on this afternoon's
agenda:

The scientist's approach to the origin of life is not in need
of an exhaustive definition of what life is. We must attack
from the naturalistic point of view, namely, that principles
unknown or unknowable to science cannot be used to solve
the problem. In other words, we proceed under the assump-
tion that life is a process that escapes at present our com-
plete understanding only for reasons of its complexity.

Muller: I think that, in the course of discussing the origin of life,
we shall necessarily come closer to a definition of what life is, so that
it is not necessary to define it now. I think the most fundamental
property distinguishing a living thing — and that can therefore be used
to define life — is its ability to form copies of itself. We call this "re-
production"; but such copies must also include innovations — muta-
tions — that distinguish a given living thing from its parents. It is this
property of not merely reproducing itself but also reproducing its mu-
tant types that inevitably led the first multiplying objects through the
three-, four-, or five-billion-year course of evolution by which all
present-day living things, including ourselves, have gradually taken
shape under the directing influence of natural selection. Natural selec-
tion could not go on without the necessary basis of an ability or faculty
of the material to copy not merely itself but its variations. That, I
think, is the heart of life, and such material, when it arose, is rightly
called "living."

Gerard: I should want a little more said before I am quite willing
to call matter "living." Perhaps this is a good opportunity to make the
point that, while one has to think and use words in terms of fairly
sharp categories, in reality there are always transitions and continua.
It may be a little unwise to think of life and not-life as if these sud-
denly were or suddenly were not — aside from all the vast changes
that have occurred in living things since the appearance of anything
that we should agree was living. Not as a geneticist or a microbiologist
but as one dealing primarily with more complex organisms, I am cer-
tainly aware of some other properties, even of simple organisms, which
I should like to see included in any definition of life.

You have certainly put your hand on the essence of life in this ability
to reproduce — and reproduce not only substance but pattern. But I
should also like to think of life as something that is going on: there

72 • ISSUES IN EVOLUTION

must be some kind of dynamic equilibrium, a flow of matter and
energy through the system. Moreover, a Uving system maintains its
integrity. It has an equiUbrium state and either maintains that state
or attempts to return to it when displaced by the impact of environ-
mental stimuli. So I should include dynamic equilibrium and the
ability to use its own energy to restore disturbances — which is called
"adaptive amplification" — as well as specific synthesis. Then I should
like to add still another quahty. I think there must be a certain level
or architectural complexity — levels upon levels upon levels. One has
subnucleons in a nucleus, and these in an atom, and atoms in a mole-
cule, and molecules in certain patterned groups, and these in still
larger patterned groups; and only when a system has gone quite a
long way in that direction of onion skin around onion skin do I think
you could reasonably call it living.

Shapley: You make life sound difficult.

Gerard: It is.

Gaffron: Matter can practically always be defined in terms of
physics, chemistry, and biochemistry. This certainly is not enough to
define life. We might ask: If we ingest food, at what moment does the
food become living? Of course it never does. One could follow a parti-
cle of assimilated food, no matter how complex, and wherever one
finds it in the living organism, it is dead. It is the process in which it
takes part that defines life, and not the matter of which it is composed.
One may freeze a cell at such low temperature that every reaction
ceases. No one could distinguish this cell from a dead one. To see
whether it is alive or has the capacity of being alive, one would have
to bring the cell back to normal temperature and see whether it still
does what it is expected to do: to grow and, particularly, to multiply.
So the essence of fife is found in the process of living and not in any
constituents of living cells.

Gerard: Your frozen cell, which is sufficiently frozen so that noth-
ing is happening in it, when warmed up, will presumably (if it is still
aUve) show certain processes that a dead cell under the same condi-
tions will not show. Now, what is the difference between the dormant
and the dead cell?

Gaffron: When defrosted, the dead cell will disintegrate, and the
dormant cell will multiply.

Gerard: This is good operationalism.

Muller: I wish to register my disagreement with nearly everything
Gerard said. In my opinion all the properties he mentioned are results
of the evolution of living matter by the mechanism that Darwin called
"natural selection." We do not have an original adaptiveness on the
part of life, but adaptation comes as a result of evolution.

PANEL ONE: THE ORIGIN OF LIFE • 73

Prosser: My definition of life tends to be a little closer to Gerard's
than to Muller's, because I think integration is the term that best
covers our ignorance of life. Perhaps it would be useful here to refer
to the concept of emergent properties. With each level of increasing
complexity of organization, properties emerge that certainly could
not have been predicted from the properties of the subunits. Molecules
have different properties from atoms, macromolecules add new com-
plexities, subcellular particles are organized chemical systems, and
intact cells are much more than the sum of their parts.

Gerard: I think that this discussion brings out the point that the
definition of life is a problem of where along a continuum you wish
to draw a line. This, of course, is a matter of definition and therefore
an individual option. This question of a sharp break or a transition or,
as Prosser put it, the emergence of something new is going to appear
in almost every panel. It is a choice between demanding the full thing
and taking a preliminary stage. Here, one could speak of "proto-life."
If you wish to define proto-life as having just the limited properties you
specify, then I am happy. If you don't wish to include the other prop-
erties as minimal, that is your privilege. I think it should be made
clear that these are successive demands we are making about when we
wish to call a thing "living."

Muller: I should draw the line where the Darwinian process of
natural selection begins to come in, and that is at the appearance of
replication of the self-copying kind — that is, the replication of muta-
tions.

Shapley: I agree. I think we all agree on the really basic points;
and our areas of disagreement are often, in a way, not the most im-
portant. To reiterate the second topic for discussion:

Darwinian evolution is now considered a fact and is the
basis of modern biology. On the other hand, any answer to
the question of what happened before Darwinian evolution
began is largely speculation. No existing and recognized
forms of life are primitive enough to be considered related
to any primordial organism or the first living cell. The
viruses, which are not cells but are apparently related to
the most important constituents of living cells, namely, the
genes, exhibit attributes of living things only as long as
they interact with the structure of a living cell.

Evans: I think one should approach living systems first in terms of
their material properties. The chemical analysis of living things — at
the level where everyone agrees that a given thing is living — always
discloses at least three components: proteins, nucleic acids, and some

74 ■ ISSUES IN EVOLUTION

device or mechanism that serves as energy source. This last compo-
nent is essential because the organization that is the essence of the
living cell is unstable and can be maintained only by the continuous
use of some sort of energy. Although these three components are pres-
ent in all living forms, they can also be found, of course, in non-living
systems.

So far as pre-Darwinian evolution is concerned, viruses (assuming
that they are all alike) are frequently considered possible examples of
what might be involved in the transition from non-living to living.
Some of the simple viruses can be isolated and shown to be nothing
more than supermolecules that can be taken apart and put back to-
gether again. In this isolated condition, they have no energy source
and, from that standpoint, are non-Hving. When introduced into an
appropriate host cell, however, the virus replicates by using the ma-
chinery and material of the organism it parasitizes. Under these cir-
cumstances the virus is able not only to repHcate but to mutate as well;
and one can regard the virus and host cell together as forming a living
system. It should be emphasized, however, that these facts do not in
themselves support the view that the evolutionary status of the virus
represents a transition from non-living to living.

Gaffron: I think my position on the definition of life is supported
by what Evans just said. What counts is the special organization that
makes a certain way of action possible, rather than the matter involved.

Shapley: What would you say are the origins or proposed origins
of viruses?

Evans: To the extent that we know them, viruses are proteins and
nucleic acid.

Shapley: I wonder if anybody would Uke to know what an expert
means by "nucleic acid."

Evans: We have a model of nucleic acid here. This is what is known
as DNA, deoxynucleic acid, one of the two types occurring in cells.
As you can see from the model, this is a large, complex molecule. DNA
exists in the form of a double helix, the two helical strands being held
together by secondary chemical forces. In terms of its chemical com-
position it contains variable amounts of four nitrogenous compo-
nents, which are referred to as the "nitrogen bases." These various com-
ponents are specifically arranged to form the strands of the nucleic
acid helix; and it is in the specific number and order of these com-
ponents that the various kinds of nucleic acids differ from each other.
We believe that the gene is equivalent to DNA and that one gene dif-
fers from another through specific differences in the number and
arrangement of the various components of the nucleic acid molecule.

PANEL ONE: THE ORIGIN OF LIFE ■ 75

Gerard: What do we mean by Darwinian evolution? Is the term
used here to narrow the total scope of evolution, excluding the evolu-
tion of stars and rocks, or is it more specific than that?

Dobzhansky: It means evolution by natural selection.

Shapley: Biological evolution?

Dobzhansky: Natural selection is the most miportant criterion.

Gerard: Involving genetic mechanisms?

Dobzhansky: Yes.

Shapley: There is natural selection in the solar system. But you
want to keep it biological?

Dobzhansky: I doubt that.

Muller: Natural selection applies to multiplying things — things
that multiply their own variations.

Gerard: Would you include specifically the genetic element?

Muller: Only that.

Gerard: Because we also see evolution of living things that may
not involve genetic mechanisms. That is not Darwinian?

Muller: Not for our present purposes.

Shapley: I have heard Muller say he had a definite line between
the living and the non-living. A good many people think that livingness
increased gradually; but you have a definite line between the live and
the dead.

Muller: Yes. Where there is replication of mutations.

Shapley: We shall go on to topic No. 3:

The now dominant idea that living things originated from
non-living matter is a consequence of our knowledge of the
earlier and later phases of the natural history of the earth
— the former as concerned with cosmological inorganic
evolution, and the latter with what happened, once life had
appeared on earth. The assumption that life originated from
non-living matter must be made by the modern scientist
if he believes that the question "What is life?" belongs in
the natural sciences at all.

Gaffron: a natural scientist who wants to study this evolutionary
process has no choice but to start and to proceed from the assumption
that the living came from the non-living. This in spite of the fact that
what stares him in the eye — all life about him — is so fantastically
complex that it is hard for him to believe it truly happened.

Gerard: With a fully developed situation, it is extremely hard to
see how it started. If I look at Gaffron, it is very hard for me to think
how he got that way. But I am sure he did.

76 ' ISSUES IN EVOLUTION

Gaffron : In a very natural way.

Shapley: Our topic No. 4 states:

Therefore, the origin of life presupposes, first of all, the
natural accumulation of suitable raw materials. Astronomy
and chemical geology provide methods for solving this ques-
tion. Further presupposed is a gradual evolution of increas-
ingly complex organic systems from the raw materials until
a self-contained unit appears which we would be willing to
recognize as a living thing. To attack this problem from the
side of living things, microbiology, biochemistry, and ge-
netics provide the tools.

We seem to agree pretty well on that statement, and therefore we
move on to No. 5, which is the heart of this afternoon's session:

Proceeding from this basis, we may subdivide the problem
into technical questions that are amenable to straightfor-
ward scientific research. For instance:

A. Did the early conditions on earth favor the accumula-
tion of organic substances? What were these conditions?

Gaffron: About thirty years ago it was thought that if life origi-
nated from non-living matter, carbon dioxide was the most important
substance involved. One knew that carbon dioxide was an inorganic
substance which illuminated plants convert in a miraculous way into
foodstuffs and living tissue. A direct conversion of the carbon dioxide
present in the early atmosphere of the earth, with the aid of ultraviolet
light and water, into something organic was considered the beginning
not only of organic substances but of life itself. In the 1920's, how-
ever, both A. I. Oparin and J. B. S. Haldane saw that an original at-
mosphere without much carbon dioxide would conform more closely
to the findings of the geochemists. According to the latter, in particu-
lar H. Urey, the planets started with an enormous surplus of free hy-
drogen; given high temperature, a long period of time, and an excess
of hydrogen, everything that could combine with hydrogen would do
so. Carbon would become, not carbon dioxide, but methane; nitro-
gen would not be nitrogen, but ammonia; and oxygen would be re-
duced to water. So the early atmosphere of the earth must have con-
sisted of hydrogen, ammonia, methane, and water vapor.

Of the various theories concerning the composition of the original
atmosphere, Urey's hypothesis has become the most favored, because
it was tested experimentally and found to be conducive to the forma-
tion of organic material. The experiment was done here at the Uni-
versity of Chicago by Stanley Miller, who subjected a mixture of hy-

PANEL ONE: THE ORIGIN OF LIFE ■ 77

drogen, water vapor, ammonia, and methane to electrical discharges.
Ultraviolet light might be used instead, but in the laboratory it is
more practical to work with electrical discharges, which would be
equivalent to lightning in the outside world. As expected, organic sub-
stances were formed.

Shapley: The Stanley Miller experiments in Harold Urey's labora-
tory in 1953 and 1954 were remarkable. They radiated in this labora-
tory the gases Gaffron mentioned as constituting the main part of the
atmosphere of the earth a few thousand million years ago.

Harold Urey was in Boston at a meeting on the climatic conditions
necessary for the origin of life on this and other planets. We had quite
a conference; and I remember George Wald asked me as an astrono-
mer how much time separated the forming of the earth's crust and the
beginning of life here. I asked him when life began; he gave it a billion
and a half years (I think it would be a bit more than that now) . Being
generous, I said, "I will give you two billion years," and he got off
a nice phrase: "Two billion years. That is just wonderful for the prob-
lem of the origin of life. In two billion years the impossible becomes
inevitable."

Now this Miller-Urey experiment has been repeated in Germany
and in Russia, at Yale, at the Oak Ridge Laboratory, and especially by
P. H. Abelson in Washington, using different mixtures and always
coming out with these organic substances.

Gaffron: Prosser, would you like to comment on the minor point,
whether carbon dioxide was present in the early atmosphere? Actually,
carbon dioxide must have been present all the time or at least have
been formed before it was re-reduced; otherwise we could not have it in
the form of the carboxyl group of organic acids.

Prosser: This is a problem of energy sources. The ultraviolet
source ceased being effective when the oxygen layer became a filter
that prevented ultraviolet light from reaching the earth. Miller's ex-
periment showed that carboxyls can be formed from an atmosphere
lacking carbon dioxide and containing oxygen as water. Presumably,
energy was stored in organic compounds, perhaps in high-energy phos-
phates. Some of this energy was released by decarboxylating reactions,
and carbon dioxide was liberated. Urey has also shown how carbon
dioxide could have been formed from the elementary compounds.
Some oxygen could have been released by photochemical reactions
prior to true photosynthesis.

Gaffron: We should mention very briefly that if a certain reaction
is not possible in the Urey atmosphere, one might try adding other
substances to make it take place.
Shapley: Especially the sulfides.

I

78 • ISSUES IN EVOLUTION

Gerard: As this discussion developed, I was struck by the real
power of science compared with other approaches to knowledge and
understanding. Not many years ago, one would have said that we were
dealing with events in the almost infinite past and that what could or
could not happen would forever be a matter of guess. One finds again
this gradualism you brought out earlier, Gaffron — little by little, one
makes a tremendous jump. Little by little, we are coming to see that
these things were possible. Things that were once matters of observa-
tion and calculation are now matters of experiment. It is a great satis-
faction to find science able to penetrate experimentally into these vast
distances of time and space.

Shapley: It is marvelous. I predicted not very long ago — a year
ago — that this Miller experiment is something the youth of our high
schools and secondary schools in general might do within a very few
years. Two weeks ago, at Dayton, Ohio, I was told of a youth who
has actually carried it through. Now I don't think he has fully analyzed
the organic material involved, but he carried out the Miller experiment
in the high-school laboratory. And this is going to become common-
place.

Gaffron: Unfortunately. Because, contrary to notions now be-
coming popular, it does not solve the problem of life. These substances
are quite dead. From the point of view of a misleading oversimplifica-
tion, it would have been even better if we had not found anything as
easy to do, because then the difficulty of the true question would not
have been obscured at the very beginning. What the Miller experiment
does is to allow us to proceed at once to the very point where the
problem of life becomes interesting.

Shapley: If there weren't other people here, I should say: Non-
sense. We'll get together later. A second technical question:

B. Were the first organic compounds of such kind that they
could be readily transformed mto parts of Hving things?

Gaffron: The Urey-Miller experiment showed that organic ma-
terial suitable for further evolution will be produced in a Urey atmos-
phere. Miller obtained acetic acid, other aliphatic acids, and amino
acids. These substances constitute an excellent nutrient medium for
many bacteria. Molecules like acetic acid or glycine, the simplest
amino acid, are used by the modern cell to build up such complex or-
ganic molecules as porphyrins, iron porphyrins, and magnesium por-
phyrins — usually known as "chlorophylls." These substances play im-
portant roles in the metabolism of most living cells. Perhaps Evans
could enlarge on this.

PANEL ONE: THE ORIGIN OF LIFE • 79

Evans: Miller and Urey found large amounts of the amino acid
glycine as well as acetic acid, glutamic acid, and other substances.
We know that the purine base (which I have already pointed out as
part of the nucleic acid molecule) can be synthesized in living cells
from a number of simpler compounds. The largest part of the purine
skeleton comes from glycine, and additional carbon and nitrogen
come from formaldehyde, glutamic, and aspartic acids. All these sub-
stances are produced in the Miller experiment. A number of these
same products are also precursors of the pyrimidine portion of the
nucleic acid. As for proteins, these are large molecules made up of
different numbers and kinds of amino acids — a number of which also
occur as products of this experiment. We see, then, that the materials
formed in the Miller experiment are precisely those which serve as
precursors for the formation of nucleic acids and proteins in living
cells.

Shapley: Very well. We will try item C:

C. At what stage in this development could one assume a
complexity that guaranteed self-replication?

Muller: I should say that one could assume such a complexity at
the stage that Evans was talking about, provided that the materials
were afforded for the coming-together of the chemical groupings in
this fashion. As yet, no protein need be there. In other words, we have
here only the coming-together into chains of the chemical groups we
call "nucleotides." They don't yet have to be even in the form of the
double chain shown in Evans' model. That, in my opinion— which is
not merely an opinion, nor solitary — is the point at which, under spe-
cial conditions in the medium that must have existed on the earth at
the time we are speaking of, the chain of nucleotides would have been
able to replicate. Now the beginning of that replication is already
shown here in the DNA model, because, as you see, this chain is
double.

This general idea goes back some forty years to the geneticists' ob-
servations that only in the chromosomes (and in a little other material
we have since found to contain substances identical with those of the
chromosomes) does one find the property of replication of mutations
—that is, self-copying and self-copying of changes— and, therefore,
the possibility of Darwinian evolution.

Now you may say: Today this material cannot replicate unless it
has protein and other things with it. Of course, it can't replicate as we
are accustomed to seeing it done, but there you have the basis of repli-
cation. And it has already been found in the laboratory that these

80 • ISSUES IN EVOLUTION

strings of nucleic acids are able to select free units (nucleotides) from
the medium and arrange them into strings of nucleotides with a pattern
like their own. In fact, the pattern is complementary to their own, in
a way that it would take too much time to describe here. Thus two
spirals are formed, which are complementary rather than identical.
Then, when these separate, the first spiral again chooses other nucleo-
tides to form a complement to it and then separates, while the other
forms the complement to the complement. So, you see, you get the
original back again, and, by a two-step process, you obtain an exact
repHcation.

Here, then, is a sharp breaking point, constituting the beginning of
Darwinian evolution. It is this mechanism that has enabled living
things so far to surpass non-living things in their complexity of or-
ganization and adaptation that we distinguish them by the special term
"living." The inherent properties of these nucleotide chains have led to
such complexities as to put their later developments out of the class of
the inanimate from which they arose.

Gerard: At what stage of complexity do you have guaranteed self-
replication? For example, why is not the replication of the architec-
ture of a crystal or the replication of a branching polymer from mono-
mers, which depends on the pre-existing polymer, life? What is your
additional criterion?

Muller: The additional criterion is that it must be self-copying,
in the sense that if you introduce a change, it repUcates that innova-
tion, too. It replicates the new type.

Gerard: I think that happens with some of the branching polymers,
when accidental misbranching occurs and is replicated from then on.
This happens with some of the synthetic processes that chemists use.
Isn't that so, Evans?

Evans: A mutation is a failure in copying — that is, the copy is
not quite exact. This can occur because the copying mechanism is
faulty or, as one probably does with mutagenic agents, by altering a
portion of the nucleic acid polymer that is the model for copying. Once
you have the faulty copy, it is then replicated as such, and the altera-
tion is perpetuated.

Muller: Yes, that is the important point. Everything in the world
can change, but this material is made in such a way that, after it
changes, it then reproduces the new thing, and that quality is not
known in anything except nucleotide change of arrangement.

Gerard: In branching polymers that happens.

Muller: I think not.

Evans: I am not sure what you are driving at.

Gerard: For example, in synthetic factories where they make plas-

PANEL ONE: THE ORIGIN OF LIFE • 81

tics or rubber or something like that, I understand that if the reaction
starts going wrong, the branching, instead of the straight-chain, poly-
mers will continue to form from that point on. This is exactly like a
virus with a mutation that goes on reproducing itself. Sometimes they
have to clean the whole thing out and destroy these molecular nuclei
and start again.

Evans: I think that is true.

Gerard: It seems to me that this is exactly the same thing.

Muller: No, I would not admit that, because, after being changed,
the nucleotide chain replicates the changed thing.

Gerard: It keeps making the same error.

Muller: The same error? You definitely know that for the plastics?

Gerard: I think so. (I know very few things definitely.)

Evans: It has to keep on replicating.

Gerard: In the same mode, the same error.

Evans: An essential feature of the system we are discussing is that
replication must continue. Your analogy seems to involve a continu-
ing process and to that extent, I think, is not incorrect. We know a num-
ber of so-called autocatalytic reactions — such as the conversion of
pepsinogen to pepsin— in which the product of the reaction catalyzes
the conversion of the precursor into the substance itself. It would be
possible, I think, for a small alteration in the autocatalytic molecule
to let the autocatalysis still continue. But I think that any major change
in the structure of the autocatalytic molecule would stop the reaction
entirely. And the ability for continuous mutation seems to be an in-
herent characteristic of living cells.

Gerard: Let me put it this way: Ordinarily, the process forms
polymer A. If a molecule of polymer B gets into the system, the
process now forms polymer B and goes on doing that. And this poly-
mer B can form "spontaneously" as a result of aberrant circumstances,
and then it continues.

Evans: When chemical systems of a certain specific character--
nucleic acids — replicate themselves, Muller chooses to call this "life."

Gerard: I was asking at what level it gets to that.

Muller: At the level where an unlimited number of changes in
pattern are possible, each of which is self -replicating. This chain can
be of unlimited length, and its four different kinds of nucleotides can
be arranged in any order. Whatever that order is, is the order that will
be replicated, with the exception of the occasional mutations. "Guaran-
teed," I admit, is a matter of degree. I am sure that when these first
arose, self-replication was less rigorously "guaranteed" than now,
because changes have been selected that increase its stability and
guarantee it better, including the "adoption" of protein into it.

82 ■ ISSUES IN EVOLUTION

Gaffron: The preliminary stage might have been the manufacture
of enormous amounts of similar, but not identical, compounds.

Muller: It is the copying of the pattern per se that is important in
allowing natural selection to act.

Gaffron: Yes. You would say, then, that the transition from non-
living to living occurred just at the point where similar, but not identi-
cal, things appeared?

Muller: It has to be identical in large measure; otherwise it does
not have genetic continuity and cannot be subject to natural selection.

Gaffron: But the selection might be chemical. We are talking here
about an early stage of evolution based on the principle of selection,
where the selection proceeds by chemical action, thus providing op-
portunity for molecules of the self-repHcating kind first to have a
chance to accumulate.

Muller: We have to distinguish between two kinds of selection:
merely chemical selection and Darwinian natural selection. There is
a very sharp distinction there.

Shapley: When did natural selection begin?

Muller: With the nucleotide chain.

Gerard: I think Gaffron impHed that it began before that.

Gaffron: I think that there is first a chemical selection, starting
with the solubility of molecules in water.

Dobzhansky: I should like to support Muller. "Chemical selec-
tion" is a misuse of the term, if you mean "natural selection."

Shapley: Chemical selection is natural.

Dobzhansky: Natural selection in the Darwinian sense is differ-
ential reproduction, and this is possible only with self-producing en-
tities of whatever kind.

Gaffron: But we are pre-Darwinian here.

Prosser: I wonder whether there is not a clear distinction between
polymerization and replication in the sense used for DNA. The per-
petuation of error in the two cases might be distinguished on this basis:
in polymerization, every time a new chain is manufactured or ex-
tended, the same mutation is repeated, whereas after mutation has
occurred in a replicating DNA chain, one has not a new mutation
every time but a copying of the original error, as from a template.
The coilmg of artificial polyribonucleotides in helical paired structures
has been obtained by Rich.

Gerard: I don't think that distinction is valid, because you have
a new set of genes that leads to a new set of molecules that aives you
the phenotypic mutant. ^

Shapley: I just asked Gaffron whether that DNA model is what
we are made of. Aren't the units much longer than that? He says that
they are indefinite in length.

PANEL ONE: THE ORIGIN OF LIFE • 83

Evans: Not indefinite. The size of the DNA molecule apparently
depends on its particular function. Actually, in terms of genetic com-
bination, genetic units can be made up of a fairly small number — five,
six, up to a hundred — of nucleotide pairs. These constitute the coding
mechanism for a specific biological feature of a living organism.
Shapley: How many turns have the small spirals?
Evans: With the bacterial viruses, there is a question whether the
DNA is in one piece or a number of pieces. If it is one piece, it is a
very large piece indeed.

Gaffron: Would it not be an interestmg proposition to prove that
selection on the level of spontaneously formed DNA molecules should
never actually have occurred because of the improbability that mole-
cules of this enormous size would come into existence in the first place?
Muller: That is exactly why we need the process of Darwinian
natural selection. What you have in the first place is only a few of the
nucleotides because of this impossibility of getting everything just
right to begin with. But, having the ability to undergo Darwinian
natural selection, then the chain can, step by step, add to its size and
improve its pattern.

Gaffron: Then you would attribute this power of self-duplication
to a very short nucleotide chain?

Muller: A. Kornberg has shown it to occur even with only two
or three nucleotides joined together. So you come down to something
that is not to be classified separately from ordinary organic chemicals
except in the potentiality for further evolution that this property gives
it. In other words, one might define life as something able to undergo
biological evolution — Darwinian natural selection.

Gaffron: Then macromolecules appeared only as a consequence of
evolution. It follows that the organization to which we attribute life
could have been formed by much simpler molecules in protein and
nucleic acid form?

Muller: The beginning of it must have been so, yes.
Prosser: The distinction between the properties of proteins and
nucleic acids has been mentioned, but it cannot be overemphasized.
Proteins grow by polymerization and are synthesized from free amino
acids. They do not duplicate in the same sense that a chain of nucleo-
tides replicates, by adding corresponding components (purines-pyrimi-
dines) and then splitting into two chains. Also, I think the size of the
chain is not critical. Replication may well first have happened with
relatively short chains. Perhaps Evans might comment on the recent
observations by Benzer.

Evans: One should remember that, until recently, the chemical
structure of nucleic acids was believed to involve a relatively simple
type of molecule and that it was impossible to explain how such a

84 ■ ISSUES IN EVOLUTION

structure could exist in the large number of variations required for
the molecular basis of the gene. Since the proteins are made up of a
large number of amino acids in different amounts, it was possible
to assume that the protein molecules could vary to the enormous ex-
tent required for any molecular basis for the genetic material. The
structure of the nucleic acids as conceived at present, however, is
such that it can produce the necessary structural variation, although
the number of components constituting the nucleic acid is far less than
that in the proteins. For example, a gene (made up of nucleic acid)
must be capable of carrying the information involved in the structure
of a given protein made up of some hundreds of the twenty different
amino acids. It is possible to devise a coding arrangement of the four
variables in nucleic acid structure that will uniquely define the twenty
amino acids that occur in protein.

There has been a shift in emphasis, therefore, in the last ten or fifteen
years. Earlier, the molecular structure of nucleic acid seemed inca-
pable of accounting for the necessary variations. This is no longer the
case, and it now appears that we need look no farther than this chemi-
cal structure of DNA for a basis for all genetic information, with five
or six nucleotide units being enough to define the particular bit of in-
formation.

Shapley: What about single-strand DNA?

Evans: Investigators in California have recently described a virus
in which the nucleic acid of the DNA type appears to consist of a
single strand. But I am not prepared to predict what effect, if any,
this has on our current idea of DNA structure. Certainly, the available
evidence suggests that the general features of the structure as we con-
ceive it are correct.

Shapley: Do you think you defined DNA and RNA sufficiently?
Maybe I wasn't listening, but I still don't know what they are.

Evans: The two types of nucleic acid are distinguished primarily by
the nature of their sugars, DNA having deoxyribose, and RNA, ribose.
That is, in the sugar characteristic of DNA the hydroxyl group is
missing from the second carbon atom. They also differ in the nature
of the nitrogen-containing basis. RNA appears to have a structure
similar to that of DNA, although our detailed knowledge is less cer-
tain. By and large, the RNA is present in the cytoplasm of cells, while
the DNA is present in the nucleus and is identified with the genetic
material itself.

Shapley: With the genes?

Evans: Yes.

Muller: Genes can sometimes be composed of RNA.

Evans: I should add that viruses apparently contain either one or

PANEL ONE: THE ORIGIN OF LIFE • 85

the other type of nucleic acid — never both. In the poHomyeUtis and
tobacco mosaic virus, the nucleic acid is of the RNA type.

Shapley: What about RNA as a genetic determiner?

Evans: Although the details of the relationship are not clear, it is
certain that DNA and RNA are intimately involved in cellular activity.
One current idea is that the genetic DNA transmits its information in
some fashion to the cytoplasmic RNA, which in turn is responsible
for determining the structure of at least some of the other cellular
components. In tobacco mesaic virus, where the nucleic acid is of
the RNA type and has been shown experimentahy to be the sole de-
terminant of the structure of the progeny produced when the virus
replicates, it is clear that the RNA does have a genetic function — al-
though this may involve some interaction with the DNA genetic ma-
terial of the host cell.

Muller: I don't think we really know enough yet to decide the
details here.

Prosser: On the other hand, RNA does carry information and
serves as a template for protein synthesis in the cytoplasm of other
cells.

Shapley: The next question is:

D. What principles govern self-replicating macromole-
cules?

Prosser: I think this has already been covered. The emphasis, it
seems to me, is on duplication in the sense of forming molecules as
mirror images or to serve as a template for an opposing molecule that
then separates off.

Shapley: We move on to the next question:

E. How does the structure of nucleic acid specify biological
properties?

Evans: I have already mentioned that the specific arrangements
of the DNA molecules can dictate, for example, the structure of an
enzyme, which is a protein. One can work out a so-called "coding
system" in which arrangements of nucleotide triplets — three nucleo-
tides — will uniquely define one amino acid. In other words, by a
suitable arrangement, in groups of three, of the four variables in the
DNA structure, one can evolve a coding system that will specify
twenty, and only twenty, variations. By equating each of these twenty
variations with a specific amino acid, one has a mechanism — entirely
on paper, of course — in which specific arrangements of the four nu-
cleotide variations would completely specify the arrangement of a

86 • ISSUES IN EVOLUTION

protein molecule containing variable amounts of twenty different
units.

Muller: I agree with this, although, like many geneticists, I don't
like the terms "code" and "information." Instead of "code" I would
say "linear arrangement" — an arrangement in single file, in a line.
As you have letters coded in words, so you could figuratively call
this a "code." I don't like the word "information" because this is a
matter, not of conscious knowledge, but of physical arrangement speci-
fying another arrangement — in this particular case, that of the amino
acids.

You were discussing the arrangement of amino acids that gives a
particular protein. We must remember that not only the proteins but
also everything else in the cell result from the operation of these nu-
cleotides; and just what substances are formed, and where and when,
depends on the particular arrangement of these nucleotides in this
enormously long chain. It isn't at all solved yet just how the nucleo-
tides operate in producing these effects. However, we know that the
arrangement of nucleotides somehow determines the arrangement
of the amino acids in the protein. This in turn decides not only what
kind of hemoglobin you have but the characteristics of your skin,
brain, and everything else. All this is an enormous job for the future,
far outrunning all other problems.

I do not want to belittle any other type of work — astronomy, phys-
ics, or organic chemistry. But it is a job of a different order of magni-
tude to find out just how all the different features that are essential in
the body of a higher organism are determined by the arrangement of
these nucleotides, of which we have about four billion in line in a
single set of human chromosomes. This would fill about one hundred
Webster's dictionaries if you were to write it all down in print as fine
as that used in unabridged dictionaries. All that, taken together, is,
if you like, the code — or arrangement, I would prefer to say. We
have not only to discover that arrangement but also to find out why
that particular arrangement gives rise to all the other complications
of our bodies. At the present moment we only know that it does so,
and we can be sure that there are changes in it. As has been shown
experimentally, these are changes in linear arrangements, and even a
change in one nucleotide at one place can profoundly affect the other
substances produced in the ceU.

Shapley: Here comes a good question:

F. Are enzymes needed for the production of nucleic acids,
which are, in turn, needed for the production of enzymes?

Evans: The role of enzymes in biological reactions is to alter the
rate at which a reaction occurs; they do not create the reaction. There-

PANEL ONE: THE ORIGIN OF LIFE • 87

fore, it is an inherent property of a chemical reaction to proceed in a
certain direction; this will occur if one waits long enough. With an
enzyme present, it may occur very rapidly indeed. If it is an inherent
property of the small molecules formed in the Miller-Urey experiment
to condense and form the large protein and nucleic acid macromole-
cules, then this will occur if one waits long enough. And, if we have
a few billion years to wait, that would seem to be enough time.

Gaffron: How many billion years are available, Shapley?

Shapley: What do you want; what is your order? There are not
too many, to be sure.

Muller: Might I make a point? Here I accept degrees. You can
have a more or a less efficient enzyme as a catalyst; and undoubtedly
before our present very much improved enzymes came into existence
there were much cruder precursors, which the nucleotide chains were
able to produce.

Gaffron: The particular nucleotide that first invented its own
enzyme had an enormous advantage over all the others.

Shapley: The survival of the most active. While enzymes are
needed for production of nucleic acids, the acids are not, in turn,
needed for fast production of enzymes?

Muller: According to this view, enzymes are not needed for pro-
duction of nucleic acids.

Gaffron: You do it with time first. After a true nucleic acid
evolves in the first two billion years, it catalyzes the production of its
own enzyme; and from then on reactions move rapidly.

Evans: We are talking of reactions of which it is an inherent prop-
erty that they proceed spontaneously. It is only because these reactions
do not occur at an appreciable rate under ordinary conditions that
catalytic enzymes play such an important role in biological systems.

Muller: If each of these miUion molecules could then produce
another million molecules, thus increasing exponentially, you would
soon recognize it.

Shapley: We are dealing in astronomical numbers. Our next ques-
tion is:

G. Modern life on earth is extremely uniform in its basic
metabolic reactions. How is this to be explained? Is it to be
interpreted as a unique (highly improbable) event, or the
result of numerous chance combinations followed by selec-
tion?

Gause: One manifestation of the uniformity of life can be seen in
the optical activity of living matter — in the fact that proteins in all
living things on earth from bacteria to man are levorotatory, or left-

88 • ISSUES IN EVOLUTION

handed. I think this points to the origin of all living systems from a
common ancestor,

Darwin: If I understand him correctly, Cause is making the point
that we have only levorotatory molecules, and no dextrorotatory ones.
It seems likely that both would have arisen equally at first, but they
may have got separated one from the other, and one happened to
bump into a volcano, leaving only the other.

Shapley: That is a novel idea.

Darv^^in: We must think about how one type managed to survive,
and not the other.

Shapley: In nature we have only one, and in the laboratory we
have two: is that the idea?

Darwin: I would say that one has to believe that, chemically speak- •
ing, the right- and left-handed molecules would have been equally
good for supporting life.

Cause: It is probable that at some stage in the origin of life the:
effect of circularly polarized light contributed to the preferential de- •
velopment of one optical form of molecules in living matter at the;
expense of the other.

Darwin: I do not mean what I am going to suggest to be taken
seriously; but you might imagine that at one time life was developing
only in the Northern Hemisphere and that the earth had a strong
magnetic field that would polarize the light there right-handedly. This
might encourage the survival of the levorotatory molecules at the ex-
pense of the dextrorotatory ones. I do not think this is more than a
fantasy.

However, looking deeper, you may recall that physicists have re-
cently been much excited by the discovery of what is called the "non-
conservation of parity." It is a subtle phenomenon in the theory of
the nucleus of atoms; and I cannot describe it here, but it does mean
that right- and left-handedness are not equivalent. However, this phe-
nomenon lies very deep, and it is hardly likely to affect the present
question. It is much more likely that both rotations were produced
equally at first but that, by mere chance, one type got a better prospect
and survived, in the end killing out the other.

Gaffron: If the production of the key substance in question was
a rare event in comparison with the number and speed of reactions
that it subsequently catalyzed, the dominance of one isomer over the
other is easily explained on the basis of "first come, first served." This
holds even if the original chances for the appearance of either one
are equal. The earlier one spoils the chances for the late comer.

Shapley: You were having me eaten up in a volcano?

Darwin: I only used the volcano to express this chance for the

PANEL ONE: THE ORIGIN OF LIFE • 89

survival of one of the two by killing the other one. Am I to under-
stand Cause's point to mean that, since I am right-handed, I shall
catch a cold only from bacteria that are also right-handed?

Gaffron: Special enzymes destroy the unwanted opposite mirror-
image type. Is this a new invention or a rehc from a time when mole-
cules had to fight off their competitors?

Cause : The existence of enzymes eliminating the unwanted optical
isomers of molecules in living matter represents an important ad-
vantage that has been acquired through natural selection and contrib-
utes to the efficiency of living systems.

Caffron: The unique event that started all this might be only
the historical moment when one isomer evolved first and inhibited
the development of the otherwise equally proficient other isomer.

Cerard: Isn't there an entirely different aspect of this problem?
The question concerns the uniformity of basic metaboHc reactions
in modem life. We have been talking about a stereoisomeric aspect
of its structure. You can replace part of the substances of a human
brain cell with equivalent substances from a yeast cell, and, so far
as the chemical reactions are concerned, this mixed or hybrid machine
works. It sort of cannibalizes another cell. In basic chemical architec-
ture and in basic chemical traffic, the simple cells and the cells of
more complex organisms are essentially alike. Of course, there are
differences in the proteins and nucleic acids, but at this level the sim-
ilarities are much more striking than the differences, whereas prac-
tically all the other attributes that organisms have evolved changed
markedly with time. In behavior, in the architecture of the whole,
and in the mechanisms of maintaining equiUbrium, you find vast dif-
ferences.

I think this ties up beautifully with the point that Muller discussed
earlier, and I am delighted to agree completely with his presentation.
To follow up this matter of coding and diversification, it seems to
me that the simpler the unit with which you are dealing, the fewer
kinds there are, and the fewer are the patterns that these can be put
into. If you have four nucleic acids, you have to arrange them in
three patterns of three to get the twenty amino acids. If you have
a limited number of letters and you cannot use them in indefinite
numbers, you can get a considerably greater number of words. Now,
if you combine those words in larger constellations, you have an infin-
ity of infinity of sentences, of paragraphs, and everything else. Since
organisms are built up of successive levels of using the simpler units
in newer patterns, each new pattern increases the richness of the array
and the numbers you can have. As the possible number of kinds in-
creases, the number of individuals of that kind tends to decrease. It

I

90 ' ISSUES IN EVOLUTION

is for this reason that, at the level of chemical reactions, you find great
similarities. But in the ways that those chemical reactions have led
to morphological structures and physiological processes, one finds
vast differences. This is what one would have to expect from the na-
ture of the organization of living things.

Prosser: I should like to emphasize that point. We have been talk-
ing about the nucleic acids and proteins as if these were the only con-
stituents of living material. Certainly, during the long period of chem-
ical evolution, a great host of other organic compounds appeared.
It is sometimes said that evolution might have been accepted more
readily if Darwin had based his presentation on the similarity of all
living things rather than on their diversity. This common chemical
basis of all living things should be emphasized. As biologists, we some-
times fail to realize that biochemically and biophysically the most
important and extensive evolution occurred before there were any
living things we would recognize as such.

Shapley: We entered life uniquely, and that was a highly profit-
able event; and then there were numerous changes, followed by selec-
tion. I think we have touched this subject fairly well, but I don't be-
lieve we have a final answer.

Our next question is:

H. Can life originate under present conditions on earth?

Gaffron: We all have learned that Pasteur disproved the notion
that the simplest organisms we know could appear spontaneously.
He showed that a cell comes only from another cell of the same kind.
We therefore moved away from that kind of spontaneous generation.
We no longer believe in the sudden appearance of a micro-organism
but prefer, instead, something like Muller's self-duplicating, very small,
nucleic acid screw. From this point of view, one could reopen the
question of life originating at the present time.

We know that the atmosphere of the earth has changed enormously.
The accumulation of organic molecules dissolved in the ocean, which
we had at the beginning, probably would not occur now, when there
is so much oxygen on earth. Today, organic substances simply are
not stable. If by pure chance an organic molecule approaching that
described by Muller should appear, either it would die of malnutrition
(there would not be enough free organic material for it to multiply
with), or it would be oxidized. Organic material disappears by be-
ing eaten, by being burned, or by slow oxidation — which is still a very
fast process, considering the millions and billions of years we are
talking about.

Let us assume that atomic radiation has killed everything on earth

PANEL ONE: THE ORIGIN OF LIFE • 91

(which is unlikely, since some bacteria might survive). The chance
that life could evolve a second time would depend on whether all
the oxygen on earth was used up in the oxidation of organic matter.
I have not made the appropriate calculation. We ought to know
whether the combustion of the organic material now present on earth
would remove all oxygen from the atmosphere. If so, it would mean
that the short-wave ultraviolet radiation could penetrate again to
the earth's solid surface. Apart from the presence of oxygen, the ab-
sence of free hydrogen presents an even greater difficulty. The orig-
inal hydrogen atmosphere constituted a store of free energy to work
with. This has disappeared. Therefore, under present conditions on
earth, we should not expect life to evolve a second time spontaneously,
once what is now living has been destroyed.

Another possibility, however, is the creation of life in the labora-
tory. The first step to attempt this is the Miller experiment. Every-
thing that we are now discussing has been learned in the last thirty
years or so. According to Oppenheimer, the increase in knowledge
is such that every ten years we know twice as much as we knew ten
years earlier. If this is so, I am quite hopeful that we shall discover
one by one the conditions that were most favorable for the creation
of life; and, finally, in the laboratory, we might someday reach the
point where Muller's early nuclear type begins to multiply — that is,
to feed on unorganized organic matter and incorporate this into it-
self: a conversion of disorder into order, similar to the growth of
bacteria, which we would all agree to call a living action.

Gerard: I think this is a very beautiful picture, if an unhappy
one. Incidentally, on the exponential rise of science Derek Price has
shown that we seem to have reached the inflection point, where one
or two more doublings in about fifteen years will not keep up the rate.
It is beginning to slope off.

I am sure Gaffron won't mind my suggesting that Pasteur did not
prove that life cannot originate; what he did prove was that reports
of the spontaneous origin of life were due to errors and the admission
of pre-existing life.

Gaffron: Strictly speaking, we can only disprove things, never
quite prove them. We fall into the habit of talking the other way
around, when something has not been disproved for a long time.

Gerard: Pasteur did not disprove the possibility of forming life
under the kinds of conditions you were talking about. He showed
that life could not be formed in a swanneck glass retort in a few
months at the temperatures of the laboratory if he did nothing more
to it. This is very different from saying that life could not conceivably
form under the conditions that now exist in the universe. However,

92 • ISSUES IN EVOLUTION

I certainly agree that the natural formation of new life is unlikely^
because, as you pointed out, larger and stronger living things would I
eat up the prototypes as these appeared; they would never have ai
chance to survive. To a certain extent, this is also true of higher species.
Some of the other panels will discuss the chances of a new form com- •
ing in and occupying an ecological niche. And it is perhaps true even i
at the social level. How do you get a piece of property when all the*
property belongs to someone?

Shapley: Then new life — what we call life — probably could not I
start on this planet any more, unless some great changes came about, ,
because either the oxygen would burn it up or the bacteria would eat :
it up. Therefore, we should take good care of the life we have andl
not destroy it.

I have been asked to poll the panel for opinions about Gaffron's;
estimate that life can be created in test tubes in a thousand years.

Gaffron: That statement probably comes from one of those news;
releases, in which an article of fifty pages is condensed into fifty
sentences and certain things simply get lost. On the same page of my
paper where I said it might be possible to solve our problem within
the next thousand years, I also said, "provided that one of these famous
improbable events is not involved." With one of those interposed, we
shall never create life.

Shapley: It seems to me you evaded that rather well.

Darv^in: Do you mean that there will have to be a gestation of
the brains of the human race for a thousand years before we see how
it can be done, or do you mean that the development itself would take
the thousand years? These are two quite different matters.

Gaffron: If we have to deal with an improbable event, which hap-
pened in the course of evolution, we have to wait a little too long
for it to happen also in the test tube.

Shapley: Do we believe that before a thousand years life can be
created in a test tube? Without any definition of what I mean by "life,"
do you wish to say "yes" or "no"?

Darwin: I don't ask for a definition of life because I am afraid
you can't define it. But, as I understand it, you think that the research-
ers will not understand what life means so as to produce it until they
have worked for a thousand years.

Dobzhansky: I am optimistic enough to believe that in a thou-
sand years we shall know a great deal that we do not know now. I
see no reason why the problem of the origin of life should take even
that long to be solved. This may be overoptimistic, but I think it is
not unjustified.

Evans: If you are talking in terms of a replicating and mutating

PANEL ONE: THE ORIGIN OF LIFE • 93

macromolecule, then I would say that it is quite possible within a
thousand years.

Gause : I think it is better to be optimistic.

Shapley: Isn't a thousand years rather long to wait for this to hap-
pen?

Gause: If we believe we can do it in a thousand years, perhaps we

shall make it in five hundred.

Gaffron: You auction it off.

Shapley: What will you give, Gerard?

Gerard: I think I am really the optimist. When you remember
that practically all we now know has been learned in 250 years of
science and most of this in one-quarter of that time; when you find

out as Panel Four will show later in the week — that the growth of

human mental capacity is perhaps very great; then Heaven knows
what can be done in a good deal less than one thousand years. I am
willing to repeat a prediction I made once about understanding one
of the important mental diseases: I said that I was quite confident
that it would be solved during my lifetime. I am safe on that.

Muller: I think I am going to shock Gerard, if he thinks he is
optimistic. My answer is that those who define life as I do will admit
that the most primitive forms of things that deserve to be called liv-
ing have already been made in the test tube by A. Romberg.

Shapley: MuUer's estimate is minus some years.

Prosser: I would certainly say that molecules of the DNA type
wiU soon be made to replicate even in the absence of appropriate
protein catalysts. Even if you add to this other criteria, such as those
Gerard stipulated earlier— most of which I will support— I think one
thousand years is pessimistic rather than optimistic. However, it must
be recognized that Miller has not found purine-pynmidme bases,
much less nucleotides, in his "primitive" system.

Shapley: I have written down: "It will be accomplished betore
the end of this century."

The next question is:

I What were the energy sources allowing for a continuous
increase in complexity of pre-biological organic systems?

That is, what is the source of energy that started all this off? We
seem to a^ree that energy is necessary to go from the inanimate, such
as this pencil, to the animate, such as Gaffron. You need some energy,
and whence Cometh that energy?

I remember discussing this problem with Harold Urey, and to-
gether we pointed out that there were at least four sources of energy.
One was already mentioned— lightning; undoubtedly there was light-

94 • ISSUES IN EVOLUTION

ning on the surface of the earth, because we had atmospheres moving
around. There would be electrical discharges. Lightning was there,
all right; it is recorded on Jupiter at the present time. A second source
is the earth's body heat, from volcanoes or hot springs. But I favor
lightning because it was established by the experiments synthesizing
amino acids. A third source was ultraviolet light from the sun. And
gamma radiation from the decay of radioactive elements is a fourth
source of energy, one that seems to be favored in the research labora-
tory of General Mills in Minneapolis. Those are four sources of en-
ergy, but the process is more complicated than I have outlined, and
somebody should pick this up and show why we must sort out these
electrical sources — or whatever the sources were — in order to keep
life going.

Gaffron: If the Miller experiment is valid — and we all beheve
it is — then, of course, the source was ultraviolet light or, let us say,
anything that would produce radicals from the otherwise colorless
atmosphere of that time.

Shapley: Miller's experiment used lightning, not ultraviolet light.

Gaffron: Yes; but since the main object is to produce radicals,
this is only an exchange of methods. Couldn't electrical discharges and
ultraviolet light be considered equivalent, if the result is simply to have
one little leg of a molecule dangling where some other thing can come
in?

Shapley: And isn't it true that you would not need ultraviolet
light if you waited long enough? All you would need is radiation from
the sun.

Gaffron: Yes; but how effective would radiation be without any
color? There might have been colored minerals, of a kind not used
today in living matter; and certainly on the surface of colored minerals
you might have had certain reactions. I don't know any examples of
this from our laboratory.

Prosser: May not porphyrins have been established fairly early
from these other sources, with the porphyrins then able to absorb
light from the sun?

Gaffron: But porphyrins are really an enormous step forward.
We are still in the colorless Urey atmosphere, where the only thing
that can happen is that some bonds of these simple molecules are
broken and then put together again in new simple combinations. The
problem here is that these new molecules would absorb more of the
long-wave ultraviolet Hght and might be broken up again. How could
these survive? One possibility is that they were washed into the ocean.
Once a molecule has a carboxyl group or an amino group attached,
it becomes water-soluble and can disappear in the depths and is there-

PANEL ONE: THE ORIGIN OF LIFE ■ 95

fore protected. In this way, a great deal of organic material could
have accumulated with the aid of lightning or ultraviolet light.

When you have larger molecules, you must handle them gently.
The chemist, of course, uses the Bunsen burner, and nature might
have used volcanoes to cook a little. In the experiments of S. W. Fox,
amino acids, when heated, combine into high molecular amino acid
polymers, which are protein-like substances. The latest information
I have on these experiments is that sulfuric acid does not favor the
polymerization but that phosphoric acid and especially polyphosphates
and organic phosphates like ATP help considerably. Now we know
that phosphoric acid in condensed form is one of the sources of en-
ergy in living cells. So this predilection for complexed or polymerized
phosphoric acid may have started very early.

Ultraviolet could not continue as a source of energy indefinitely,
because, as hydrogen slowly escaped, the atmosphere changed from
a reducing one to one in which oxygen began to accumulate. Direct
decomposition of water molecules speeded up this process. From free
oxygen, ultraviolet light formed ozone and produced in the upper at-
mosphere an ozone layer, which in turn intercepted the short ultra-
violet-wave radiation that had provided energy.

So another source of energy was necessary, and here come in
Prosser's porphyrins. Since only acetic acid and amino acid are needed
to produce organic molecules of a dye type, which absorb visible
light, here is a new energy source. There is a shift from ultraviolet
to visible light, and the amount of light available is enormous. This
might be a prototype of what we now call "photosynthesis," but the
complexity of photosynthesis clearly indicates that it appeared much
later; its origin might have been pre-cellular, but certainly it arose
by steps. I think Harold Blum was one of the first to note that the
simple one-quantum process where molecule A gets a hydrogen atom
from molecule B, which it would have to wait a million years for
without light, could take place within one second with the aid of an
illuminated dye molecule acting as an intermediary. In this way, dye-
stuffs, once formed, could speed up reactions and use ordinary day-
light as an energy source.

Shapley:

J. When and how did the change from anaerobic to aerobic
conditions occur?

One current theory about the origin of the earth and other planets
holds that a cloud of gas, as it contracted, formed the sun — or the
forerunner of the sun — and protoplanets, one of which was the earth.

96 • ISSUES IN EVOLUTION

I think some theories would say that the earth-forming nebula that
preceded what we have now was perhaps ten times as massive as the
present earth.

What was that mass made of? Hydrogen, very largely, because
the sun is mostly hydrogen. Eight-tenths of the sun and all the stars
are hydrogen. Here, on earth, hydrogen is relatively scarce and is
apt to combine with oxygen into water and with other elements; most
of the original hydrogen has escaped because the mass of the earth
is not enough to hold it down, and the sun, with its radiation, can
heat it up and speed it away. Presumably, during the first billion years
of its existence, or much less than that, the earth was steadily losing
its hydrogen. The earth shrank, and we now have left this remnant —
perhaps one-tenth — of the original earth. There is a good deal in
favor of that particular interpretation, and it explains the remarkable
fact that in the universe at large hydrogen is predominant and oxygen
relatively scarce.

Here on the face of the earth, however, oxygen forms about 50
per cent of the total. Oxygen is common; it is heavier than hydrogen
and less easily lost. Nearly one-quarter of earth's atmosphere now
is free oxygen, which was not present in the early days. The oxygen
of the atmosphere was built up in more than one way: photosynthesis,
for instance, and the dissociation of water vapor by radiation of the
sun, perhaps at the top of the atmosphere. So we look at this partic-
ular oxygen situation as a detail of the evolution of the earth. The
earth, together with its atmosphere, evolved over billions of years
by building up its content of free oxygen, where there had been prac-
tically none. I would say that the atmospheric ozone layer, which is
some ten to thirty miles above the earth's surface, is enough to shut
off the ultraviolet light, which we could not now stand but which was
probably rather important in earlier evolution. In the early days, water
— J. B. S. Haldane's "hot thin soup" — could give protection from
ultraviolet radiation.

Darwin: I wish to ask one question about the first appearance of
oxygen. I quite accept that hydrogen would leak away at the top of
the sky. Would not the next effect be for oxygen not to come into
existence but to attack the methane, break that up, and get rid of
it into water and carbon dioxide? The water would then decompose,
and the hydrogen leak away. Wouldn't it be a very long time before
oxygen appeared as 02 and 03; wouldn't it mostly go into carbon
dioxide first?

Gaffron: Oxygen in contact with carbon or organic material very
probably would react. Hence the carboxyl groups of the organic com-
pounds found in the Miller-Urey experiment.

PANEL ONE: THE ORIGIN OF LIFE ■ 97

Darwin : It might take one billion years to get rid of the methane.
We know there is methane on Jupiter, don't we?

Shapley: Methane and ammonia and water — in fact, the planet
Jupiter may be mostly ice. All Jupiter needs is for the sun to become
hot enough to get Jupiter's temperature up to liquid-water state (which
would scorch us), and then it would have all the materials to start
out a Jovian life.

Darwin: When does carbon dioxide appear in the history of earth?

Shapley: I don't know.

Gaffron: It might be after the hydrogen had disappeared and
water began to be decomposed by the ultraviolet radiation.

Shapley: It could be that, yes.

Prosser: So far we have been talking about energy sources pri-
marily for synthesis. We have been considering extra-terrestrial sources
— ultraviolet, lightning, cosmic rays — and then we considered the
fact that, as oxygen increased (perhaps by decomposition of water),
the ultraviolet would be cut off as a source of energy.

We know that life today does not rely on ultraviolet or on Ughtning
for energy. Living things make use of organic compounds formed by
photosynthesis, which store up energy and are then decomposed by
appropriate reactions; usually the energy is transferred by some in-
termediate, commonly a compound with high-energy phosphate bonds.
It is highly probable that such energy stores appeared very early in
chemical evolution and that, as these stores accumulated, energy
could be transferred for biological work from these pre-existing com-
pounds. Some of the reactions by which stored energy is released,
particularly by removal of hydrogen and transfer of energy, often
operate without oxygen and must have occurred in the anaerobic
period of evolution. This type of metaboHsm (if we can call it that)
in pro-organisms could proceed very well so long as there was an
adequate store of energy sources. As soon as oxygen began to ap-
pear, the amount of ultraviolet impinging on the air certainly de-
creased, and energy sources were no longer replenished.

Probably the more important source of oxygen was photosynthesis,
and it seems probable that this process appeared in some form, mak-
ing use of pigments or porphyrins, probably coupled with metals, well
before there were organized photosynthetic structures such as we might
consider essential for photosynthesis today. With this shift, there cer-
tainly was a change in the atmosphere. There was also a change from
anaerobic metabolism to aerobic, and it seems to me that this is a
rather critical step in chemical evolution. Virtually all living things
today have retained most of the enzymes associated with anaerobic
metabolism, and most of them have added the aerobic enzymes. As

98 • ISSUES IN EVOLUTION

we mentioned earlier, the principal classes of biochemicals were estab-
lished before there were any organisms. So it would appear that the
transition from anaerobic to aerobic conditions was a very critical
step and extended over a long period of time but that living things
have retained both types of metabolism.

While I am talking, I should like to bring up a feature of pro-or-
ganisms that has not been mentioned so far; in fact, I do not know
how this was left out as a question. It seems to me that one of the
criteria (and an important one) of living things is that they are dif-
ferent internally from the medium in which they live. In other words,
there is a surface, which in living cells we call a "cell membrane,"
that permits certain substances to pass and prevents others from pass-
ing. Not only are organic molecules retained, but some inorganic ions
become concentrated inside while others are excluded; different con-
centrations of ions inside and out are due only slightly to binding by
organic molecules but more to properties of the surface. I suggest
that the selectively permeable surface is one of the criteria that should
be applied to a pro-organism, certainly at a more complex stage of
organization than the nucleotide molecule. I should not wish to end
this discussion without emphasizing that the surface of the macro-
molecules that constituted pro-organisms was certainly there before
there were organisms.

Gause: There is one special point I should like to mention here.
It seems that the invention of cytochromes and other mechanisms
that made possible the aerobic way of life was very important in the
evolution of living matter. We can judge the importance of all these
mechanisms now by the analysis of certain retrogressions to a primi-
tive state that accompany the injury of cellular respiratory mecha-
nisms. Cancer is one of these. In tumor cells the impaired respiration
is accompanied by many losses, which make their disorganized growth
possible. This problem is of wide biological significance, and its mani-
festations can be observed in various forms of life.

Shapley: Gause is an expert on the relation of cancer to the proc-
esses we are talking about.

Evans: The aerobic process is much more effective from the stand-
point of energy supply. For example, the anaerobic use of glucose
gives only about one-eighth the energy that can be obtained aerobically.
From the standpoint of efficient utilization of foodstuffs, aerobic mech-
anisms are obviously much more efficient.

Shapley: Would you say what "aerobic" and "anaerobic" mean?

Evans: Aerobic pertains to metabolic processes requiring and us-
ing molecular oxygen, while anaerobic pertains to metabolic reac-
tions that can occur in the complete absence of oxygen.

Gause: It is clear that there are important quantitative differences

PANEL ONE: THE ORIGIN OF LIFE • 99

in the efficiency of utilization of energy under aerobic and anaerobic
ways of life. But, as Pasteur pointed out, there are also important
qualitative differences: certain processes and differentiations in liv-
ing matter can occur only in the presence of oxygen.

Gerard: In getting away from proto-life, you frightened me so
that I kept quiet for a while. But now we are up to cancer and multi-
cellular organisms, I should like to point out (this really ties back
to this question of aerobic metabolism and also back to energy sources)
a very striking thing: that this relatively complex porphyrin molecule
was used first to make chlorophyll, which captured sunlight energy
and made possible the great deployment of plants and therefore of
animals.

Second, it was the basis of most of the oxidizing enzymes in cells,
which made possible the exploitation of the aerobic mode of life and
greatly increased the rate of metabolism. And, since living things are
always meeting stresses and are always competing with each other
and since survival does depend on a certain degree of fitness, the or-
ganism that could move faster "got there fustest," and the early bird
got the worm, and all that — not worrying about the worm.

The next advance along the same line happened in multicellular
animal evolution, where, with rise in body temperature at a greater
rate, it again became necessary to get oxygen into the inner cells
that it could no longer reach through diffusion. And respiration and
circulation and the like really depended on still another biological
invention based on this same basic molecule: the invention of hemo-
globin, which made it possible for blood to carry tens or even hun-
dreds of times as much oxygen as it could carry before. And so each
step in this molecular evolution made possible new advances that
solved bottlenecks in the further advance of Uving organisms.

Prosser: It is all based on the same type of molecule.

Gerard: That's the point: all three of these inventions involve
the basic porphyrin molecule.

Gaffron: In certain bacteria one has a model of the adjustment
from anaerobic to aerobic life. So long as there is no oxygen, they
multiply very nicely at the expense of organic compounds by the in-
efficient, but quite workable, process of fermentation. As soon as
oxygen is admitted, they die. However, if the bacteria find in their
surroundings some of these porphyrin iron compounds — ordinary
hemin, for instance — they take these in and produce for themselves
the proper iron-proto-porphyrin enzymes for respiration and also en-
zymes to destroy hydrogen peroxide — should this dangerous sub-
stance be formed — and under these circumstances they are not killed
by oxygen but live happily ever after.

These bacteria must take up their porphyrins from the medium,

100 • ISSUES IN EVOLUTION

just as a diabetic needs a shot of insulin from time to time; so actu-
ally what we have here is not yet a permanent adaptation to aerobic
conditions. But, should the favorable circumstances continue long
enough, one could assume that by the process of Darwinian evolu-
tion and selection the bacteria could learn not only to use but also
to synthesize porphyrins. This is one of the possible models of a bio-
logical adjustment to the change from anaerobic to aerobic condi-
tions.

Shapley: Nature has made two major inventions — photosynthesis
and hemoglobin — and without those we wouldn't be here. I shall ask
Darwin for a comment about the next question, topic No. 6:

What is the probability of life on other planets?

Darwin: I hoped you would begin by saying how many planets
there are that could support life.

Shapley: Myriads; maybe multillions.

Darwin: 10-°?

Shapley: More than 10-° stars. And those stars are competent
to provide life for any planets around them. Probably most of them
would have planets of some sort, so your 10-° is all right.

Darwin: As I understand the question, it is whether life is an ex-
tremely improbable event or whether it could happen easily. I like
to put these things in numerical figures, which are easier to grasp.
Therefore, let me assume that it has happened only once.

Shapley: Once in 10^°?

Darwin: Let us assume that we have sent out space ships to ex-
plore all the planets in the universe where conditions could support
life and that we have found them all absolutely bare. Then we can
say that the creation of life is an extremely improbable event, having
happened only once in 10-° times.

I like to put these things in numerical form, and the easiest way
is to think of the spinning of a coin. If you spin a coin five times —
playing not with a stranger in a bar but with a trustworthy friend —
you are unlikely to get heads all five times. But once in about thirty
times you will. My calculation is that if the creation of life is an ex-
ceedingly improbable event, which has happened only once in the
whole universe, that is as though, in playing the game against the
other planets, we had won the toss about sixty times running with
no failures in between.

Shapley: That is dramatic enough. That 10^° is a hundred thou-
sand million billion — American billions.

If we are referring to the planets of this system, I would say the
chances of life are pretty dim, but not conclusive. If you will ask the

PANEL ONE: THE ORIGIN OF LIFE ■ 101

question a few years from now, we shall be able to answer it a little
better than we can now. The conditions on Mars are such that low
forms of life, like the algae, maybe mosses — very low forms like
lichens — could apparently exist. We don't know very much about
conditions on Venus, except that there is very little oxygen in its at-
mosphere and therefore not much plant life. In the future we might
penetrate the shield of clouds and learn something about the surface.

The probability of other life in our solar system is not very high;
but, with 10-" other suns and a great deal of cosmic time and the
method of the birth of planets pretty well worked out (there are two
or three methods), we could say that the probability is exceedingly
high that there is life — not our life; probably not vertebrates or any-
thing of that kind — on at least one hundred million (I use one hun-
dred million just to be conservative), a hundred million where there
has been a long evolution of organisms. This is all speculation; but
I have to call to your attention that the one place we have found life —
in fact, practice it — is just an ordinary planet around an ordinary
star — a run-of-the-mill star — which is out at the edge of a galaxy
that has at least one hundred billion other stars; and that galaxy is
one of billions. It is asking too much to think that this is the only
place. I believe you get "tails" once or twice in your sixty throws, all
right.

Darwin: I agree entirely that it is much more likely that the chances
for life are very much stronger. If you only needed to win twenty
throws instead of sixty, there would be a good chance of life on a great
many planets.

Shapley: As I understand it, you are a little stingy with life?

Darwin: It gives you much better chances.

Shapley: Oh yes, much better.

Many astronomers would say that, from the way stars are born,
every one of them would have a family of planets (unless it is a double
star that could perturb planets out of its system). That would mean a
tremendous number of stars with planets. To go from that to the
number that would have liquid water and from that to the number
where life started, of course, diminishes the chances from 10^*^ to a
mere, say, one hundred million. But those who speculate on this think
I am very conservative.

Muller: I should like to mention a hypothesis that I think is held
by a number of people, one expressed by the Burbidges in Science
about a year ago: that only in stars of what they call the third gen-
eration or later are there enough of the heavy elements to support
life as we know it and that our sun is apparently one of the oldest of
that youngest generation of stars, and therefore presents much more

102 • ISSUES IN EVOLUTION

suitable conditions for the evolution of life as we have it on earth
than the vast majority of other stars would. Do you think there is
some basis for that theory?

Shapley: That is included in my calculation. The Burbidges and
others — Fowler, Greenstein, and others — have worked out very bril-
liantly, and it seems to me very convincingly, the evidence that the
atoms of matter themselves evolve, and so evolution applies not only
to the biological world but to the world of matter. Our sun is a middle-
aged star, but we have in our catalogue at Harvard 40,000 stars whose
spectra are the same as the sun's. That, I think, is an indication that
about 10 per cent of all the stars — that is, more than 10^^ — would
be like our sun. To be like our sun and still able to carry out these
particular biological activities, I would be willing to say perhaps only
one in a million. In fact, I have said that only one in a million million
stars might support life. Therefore, life does not have to appear very
often to attain that number of a hundred million. We support the
proposition, you see, that the new work on the origin of life — like
the Miller-Urey experiment — and the new evidence of an expand-
ing universe and new evidence of the total number of stars give
us very good and convincing indications that conditions elsewhere
throughout the universe must be very favorable for life. And I think
I am doing a service to this group if I point out that you ought to be
proud you are in such a grand universe.

Dobzhansky: I was rather embarrassed to find myself on the panel
discussing the origin of life, which I know nothing about. The only
thing I hoped was that I might keep silent and look wise. One of my
distinguished colleagues told me that he doubted that I would be able
to do either; and you see he was right.

Now, I don't know the probability of life on other planets. I take
it that this probability is fairly high. But if life does exist on other
planets, and even on a very large number of these, it does not follow
that this is very much like the life we know. To put it a little more
exactly, it does not follow that the evolution of life on these other
planets has been very similar to the evolution of life on earth. Evolu-
tion is a long and complex process involving very many changes in
the genes and the nucleic acids and so forth. Now the likelihood that
these changes could have occurred twice in the same way, either on
earth or on other planets, is not great. This seems to me an important
point, because very often when people speak of life on other planets,
they automatically assume that Martians, for instance, will be pretty
much like us. This does not follow from the evidence; personally, I
think it is improbable.

PANEL ONE: THE ORIGIN OF LIFE - 103
Shapley: Topic No. 7 asks

What are the possibilities of transport of germs through
space?

Muller: Germs in space, unprotected by a good deal of solid
material around them, would be destroyed by radiation of varied
kinds — protons and photons, ultraviolet and gamma — before they
reached another planet. I do not see how they are going to get out
into space, short of something like volcanic action, in which case it
is hard to understand why they should not be killed, unless, of course,
it is done artificially.

Shapley: If it is left to nature to infect us with spores from other
planets, the probability is very slight; but if they were pushed in hard
with rockets, they might get here with proper protection. I think we
agree on that.

Gerard: What about the evidence of meteorites with living things
in them; is that vaUd or invalid?

Gaffron: Not quite living things. There are meteorites that con-
tain up to 24 per cent carbon; and this carbon is neither methane
nor a simple hydrocarbon, but rather complex organic material con-
taining nitrogen. According to Edward Anders, at the Fermi Institute,
it is 24 per cent carbon, 8 per cent hydrogen, 4 per cent nitrogen, 8.8
per cent sulfur, and 6 per cent chloride; the rest would be oxygen.
This points to a rather complex organic material, supposedly even
older than the crust of our earth.

Shapley: Carbonaceous chondrites.

Gaffron: Yes. And their age has been determined by radioac-
tivity comparisons. Some of the odors they give off on heating have
been described as garlic- and cinnamon-like.

Shapley: If it smells like garlic, it is cosmically important. We
are indebted to Anders for this new, accurate chemical analysis, which
sounds very important.

What about propelled germs? For instance, how about sending
rockets to the moon that are full of germs and causing trouble on
that body? Gause is an expert on this.

Gause: To avoid possible contamination of the moon by micro-
organisms from terrestrial materials in moon shots, a group of micro-
biologists at the Institute of Microbiology of the Academy of Science
of the Soviet Union is planning a thorough sterilization of materials
forwarded to the moon.

Shapley: Of course, they know how to do that. So apparently the
moon is all right. To me it sounds a little bit ridiculous, but probably

104 ' ISSUES IN EVOLUTION

necessary, so that when we get to the moon we shall find it unsullied.

Arrhenius is one of the persons associated with the idea of pan-
sperms in early times when it was thought that perhaps life did not
start on this earth but came in on meteorites or otherwise from other
worlds. That theory was pretty generally dropped when we learned
about cosmic radiation and other hazards. It is highly improbable
that we have any living contact with other planets around other stars.

Gaffron: Science of November 20 contains a note by Carl Sagon
on this subject. He says that if spores ever reached the moon, they
would have to be imbedded below the soil in order to survive, or they
would be destroyed very quickly by solar radiation.

Darv^in: You could guess the sort of speed at which they would
hit the moon. Did he estimate what the coUision itself would have done
to them? Couldn't this be quite enough to burn up anything inside as
well as outside?

Shapley: Yes, it would. If anything falls on the moon, it is going to
be explosive unless it comes in very slowly; but if you are ingenious,
probably you can slow up your infected rocket and come down on the
moon without burning it up.

Gaffron: Anders says that chondrites have not been internally
heated above two hundred degrees.

Shapley: Have members of the panel further points to discuss? If
not, I shall make a brief summary.

We started out by agreemg that we should not make an exhaustive
definition of what life is, because we don't agree on a definition; but
we did agree that after a thing had developed a while, we should prob-
ably all call it "living." We pointed out that Darwinian evolution is
no longer a theory but a fact; and we discussed the viruses. We pointed
out that the idea that life came from non-living matter is a consequence
of our knowledge about the inorganic world and the biological world.

We went into various questions. We agreed that the early conditions
on the earth favored an early accumulation of organic substances.
Were the first organic compounds of such kind that they could be
readily transformed into parts of living things? Yes, some of them.
What about the principles of replication governing self-regulating
molecules? We discussed that in a highly technical way. Our discussion
of how nucleic acids coat biological products was fairly technical bio-
chemistry.

Can life originate under present conditions on earth? We think the
answer is No. Too much oxygen, too many bacteria. Can it occur in
a test tube? The decision was Yes. To do it completely, however, may
take longer than we think.

We summarized the sources of energy in the origin of life and

PANEL ONE: THE ORIGIN OF LIFE ■ 105

mentioned gamma radiation, lightning, the heat of the earth, and
especially ultraviolet light from the sun.

What is the probability of life on other planets? I think we agree
(although we objected on some details) that it would be presumptuous
of us to suppose that the only life that exists is that on the earth. That
would be very improbable.

What about the possibiUty of transporting germs through space?
We think it would be hard on them. I think nobody would hold that
there is a danger of infection by germs from other planets, especially
if these came here by natural methods and were not propelled. That
led us then to the moon shots, and we were assured by Cause that
thorough sterilization was practiced in the famous Russian shot. This
is a quick summary.

Before we adjourn, I wish to ask Cause, our distinguished guest and
panelist from Moscow, if he would make some concluding remarks.

Cause: Since it seems to me that the discussion we have just had on
some problems of the origin of life was very useful, I am pleased to
say that it had much in common with, and reached almost the same
conclusions as, an earlier discussion of the origin of life, held in
Moscow, to which many American participants were invited. I hope
this is the beginning of many scientific discussions, and I hope the co-
operation now developing in various fields of science will contribute to
a better understanding between our countries.

PANEL TWO
THE EVOLUTION OF LIFE

Chairmen: Sir Julian Huxley and Alfred E. Emerson
Panelists: Daniel I. Axelrod; Theodosius Dobzhansky; E. B. Ford;
Ernst Mayr; A. J. Nicholson; Everett C. Olson; C. Ladd
Prosser; G. Ledyard Stebbins; Sewall Wright

Preamble

Biologists one hundred years after Darwin take the fact of evolution
for granted, as a necessary basis for interpreting the phenomena of life.

Life, to the biologist, denotes the totality of self-reproducing meta-
bolic organizations of matter and energy comprised under the head of
"organisms." The problems of its origin from non-living systems and
of intermediate stages between living and non-living have been dis-
cussed by Panel One. Life first appeared on this planet over 2,500,-
000,000 years ago and has been steadily evolving since then.

Evolution is definable in general terms as a one-way, irreversible
process in time, which during its course generates novelty, diversity,
and higher levels of organization. It operates in all sectors of the phe-
nomenal universe but has been most fully described and analyzed in
the biological sector.

Life appears to depend on self-replicating and self -varying (mutat-
ing) organic macromolecular strings of DNA, which also act as tem-
plates for the function of specific proteins, although RNA molecules
may also be implicated. In all organisms except viruses, genetic and
evolutionary "information" is carried by DNA organized into chromo-
somes in combination with protein.

Points for Discussion

1. One major concern of modem evolutionary biology is research
on the mechanisms of evolution, particularly as studied by experi-
ment, in the field and in the laboratory.

107

108 ■ ISSUES IN EVOLUTION

2. The production of genetic variants resulting in new genotypes is
enormously amplified by sexual recombination. This consists of i
an exchange of material between homologous gene sets. This is
perhaps an inherent property of DNA strings and certainly must
have started at an extremely early stage.

3. The self-replicating and self-varying properties of DNA inevitably
lead to natural selection — i.e., the differential survival and repro-
duction of biological variants. Mutation and recombination pro-
vide the raw materials for evolutionary change; natural selection
is the guiding, or directive, agency in such change. Other agencies,
such as random "drift," will sometimes lead to non-directive
genetic change in populations, which may be combined with di-
rective change.

Modern studies on the material basis of inheritance and on the
efficacy of natural selection rule out Lamarckian or vitalistic-
orthogenetic theories of evolution.

4. Natural selection as a mechanism for generating an extremely
high degree of improbability. Change-inhibiting (stabilizing) and
change-promoting (novelty-producing) forms of selection. Mean-
ing of biological fitness. Selection between individuals of the
same sex, within and between populations, between species and
higher taxa, between communities. Selection involving competi-
tion and selection involving co-operation.

5. Biological evolution always shows a combination of continuity
and discontinuity, a compromise between stability and change,
and an interplay between randomness and directional selection.
Indeed, all characters of all organisms represent compromises be-
tween several biological needs or values.

6. The relations of developmental (epigenetic) and physiological
processes to selection and evolution are proving to be very im-
portant: e.g., stabilization (canahzation) of developmental proc-
esses, partial simulation of Lamarckian evolution by genetic as-
similation and other evolutionary "feedback" mechanisms. The
role of pedomorphism and recapitulation in evolution.

7. Natural selection may lead to side effects, which at the time are
of no adaptive value ("correlated characters," Darwin; "conse-
quential characters," Huxley). These may later provide the basis
for adaptive change or even open the door to new major evolu-
tionary advances.

8. The evolution of sex as an illustration of evolutionary process:
"Sex" was originally a mechanism for insuring genetic recombina-
tion by interchanging portions of separate gene sets and involved
no distinction between male and female. Later came the differen-

PANEL TWO: THE EVOLUTION OF LIFE • 109

tiation of two sexes, first in respect of gametes, later of accessory,
and still later of secondary sexual characters.
9. Another major concern of modem evolutionary biology is the
study and analysis of the course of biological evolution, as actually
shown in fossils and as deducible from the data of taxonomy,
comparative anatomy and embryology, animal behavior, geo-
graphical distribution, and ecology.

10. The process of biological evolution involves the integration of
three component processes :

a. Diversification, leading to branching and to the formation of
separate and distinguishable species and higher taxa

b. Transformation, leading to detailed general adaptation, both
structural and physiological, greater efficiency of various func-
tions, more advanced and better-integrated organization, in-
cluding the organization of behavior and emergent mind (to be
discussed in detail by Panel Four)

c. Stabilization, leading to the formation of stabilized patterns of
organization at all taxonomic levels and to their persistence
indefinitely or over long periods.

11. Isolation of various kinds appears to be a prerequisite for all de-
grees of diversification by branching. Stabilization may be brought
about by a number of factors — physiological limitations, high
specialization, etc. — superposed on a successful stabilized pattern
of organization. Long-term stabilized persistence occurs not only
in reduced and relict types (e.g., ReptiUa; Xiphosura), but in new
dominant types (e.g., ants, birds). Transformation always leads
to adaptive or, better, teleonomic results.

12. Evolutionary novelty at all levels from the species up appears to
be achieved by means of breakthroughs from one stabilized sys-
tem (pattern of organization) to another. Such breakthroughs
often involve some degree of preadaptation, the employment of
pre-existing biological and chemical characters to produce novel
results. They are always unusual events (e.g., for new species)
and for major groups such as classes are very rare (e.g., from
ReptiUa to Aves and Mammalia ) .

13. Biologists are increasingly concerned with the formulation of
general rules and the study of long-term trends operating in evolu-
tion. The major trends include those toward greater size; toward
greater efficiency of particular functions, such as digestion or
locomotion; toward higher levels of organization (greater dif-
ferentiation and integration) of structure, physiology, and be-
havior; and toward the emergence of more elaborate mental func-
tions.

110 • ISSUES IN EVOLUTION

14. Some of these trends can properly be called progressive. Biologi-
cal progress may be defined, or at least described, in terms of the
upper levels of "improvement" achieved during evolution in cer-
tain properties of organisms. It is neither inevitable nor universal.
Regression in some functions may accompany advance in others
(e.g., parasites). In most groups stabilization appears to have
set in well before the Pliocene, so that no major later evolution-
ary advance for them was possible.

It is interesting to compare the criteria of advance or progress
in plant and animal evolution.

15. Biological progress is marked by the successive emergence (break-
through) of new, successful ("dominant") types. The rise of each
new dominant type alters the evolutionary-ecological pattern and
introduces new factors into the evolutionary process. The study
of the emergence and radiation of new dominant types is leading
to many important conclusions about the role of time in evolu-
tion, the different rates of evolutionary change in different groups
and in different times during the rise of single groups, and with
different environmental opportunities.

The emergence of man as the dominant type will be considered
in detail by Panel Five. Meanwhile, it has altered radically the
evolutionary-ecological situation and has rendered the emerg-
ence of any other dominant group impossible. The question
whether evolutionary change is still occurring, and by what meth-
ods, will be left for Panel Five to discuss.

16. The last few decades have witnessed the growth of a "synthetic"
theory of evolution, linking the findings of many separate disci-
plines. These include genetics, selection theory, paleontology, tax-
onomy, behavior, embryology, plant and animal physiology,
biochemistry, biogeography, and ecology. Though great progress
has been made, there are large areas in which new research and
study are needed and will undoubtedly yield fruitful results.

The Discussion

Huxley: I hope I can be as good a chairman as Shapley was yes-
terday. I rather think not; the combination of Napoleonic firmness
and humor is very difficult to emulate.

We are meeting to discuss the evolution of life, yesterday's panel
having discussed its origin. We have here a number of persons dis-
tinguished for work in various fields of biological evolution: Axelrod,
in paleobotany; Dobzhansky, in population genetics and in polymor-
phism; Ford, in genetics in nature and in relation to population; Mayr,

PANEL TWO: THE EVOLUTION OF LIFE • 111

in the formation of species in nature; Emerson, in ecology in nature.
Several of us are essentially naturalists who have gone to the labora-
tory. I have studied various things in nature; Nicholson has done the
same. Olson is interested in past nature — paleontology and fossils —
and Prosser is interested in physiological nature; Stebbins is a botani-
cal naturalist. Sewall Wright, I beheve, likes to be remembered for his
classical work on the genetics of guinea pigs, but the world will re-
member him for his immense contributions to general genetic and
selection theory.

The evolution of life is no longer a theory; it is a fact and the basis
of all our thinking. It seems extraordinary now that the mere idea
of transformation caused such an outcry and occasioned such distress
to Darwin himself.

We do not intend to get bogged down in semantics and definitions.
We began by taking certain facts for granted, and therefore we drafted
a preamble, which I shall now read to you. We say that life, to the
biologist, is not an entity but denotes the totality of self-reproducing
metabolic organizations of matter and energy, usually comprised under
the head of "organisms." The problems of its origin have already been
discussed. It first appeared on this planet about two and one-half bil-
lion years ago — probably rather more — and has been steadily evolving
since then.

By "evolution" we do not mean any mysterious force. We mean a
process. It is a one-way process in time, not irreversible in the sense
of being irrevocably determined from within but in that it appears not
to be actually reversible, as various chemical reactions are. In its
course, evolution produces a large amount of novelty and diversity
and also generates higher levels of organization. (Later on, we shall
try to see whether we can define either "higher" or "organization";
this is not very easy. ) Evolution operates everywhere, in the whole uni-
verse, but has been most fully described and analyzed in the sector
dealing with life.

As we saw yesterday, life appears to depend on self-replicating and
self -varying (or mutating) organic macromolecular strings of DNA;
and in all organisms except a few viruses, so-called genetic and evolu-
tionary "information" is carried by DNA organized into chromosomes
in combination with protein. That is the physical basis of evolution.
Stebbins: I think at the very beginning we should emphasize the
point made yesterday that organization and processes are as much a
part of life as are the life-substances — the nucleic acids. We see this,
for instance, from experiments with viruses, showing that activities
do not occur unless the nucleic acids are organized with proteins but
that the nucleic acid determines what kind of activity will take place.

112 • ISSUES IN EVOLUTION

An analogy with a corporation might be made here. The nucleic acid
is the head office, but the head office cannot function without workers,
materials, factories, and so on. I think this analogy is better than call-
ing the nucleic acid the real or the only basis of life.

Another point I think will come out in this and subsequent panels
is one that Wright has often emphasized: when we talk about evolu-
tion, we are talking about a succession of higher levels of organization,
starting with the chemical and physical level, going up through the
level of primitive one-celled organisms into the organization found in
the muscles and tissues of a higher animal and, finally, into the kinds
of organization found among animals in various sorts of social sys-
tems. Here, I think, we should qualify the statement that evolution is
irreversible, since simpler forms of organization have often come from
more complex forms. Fleas, for example, evolved from more com-
plexly organized insects; and many other examples could be cited.

Perhaps this is a good place to mention a point that Huxley raised
in Evolution: The Modem Synthesis, that any definition of evolu-
tionary progress concerns the fact that, as a result of natural selection,
species with higher levels of organization are more likely to dominate
their environment than are species with simpler levels of organization.

Huxley: Certainly, a particular direction or trend in evolution can
be reversed, but the process as a whole appears to be irreversible,
which is a different thing.

You raised a very interesting point about increase in organization.
There has been an immense increase in organization, even in the
chemical basis of life, from tiny snippets of DNA in viruses and short
strips in bacteria, to the enormous "tape recordings" in the chromo-
somes of higher animals. In the organization of this coded "informa-
tion," the size of the codebooks has multiplied from a little notebook
to volumes and multivolume encyclopedias.

I remember years ago reading of a schoolboy, asked to write an
essay on evolution, who produced one immortal sentence for the
whole of his essay: "Mr. Darwin said that the first monkey was a sort
of jelly." Well, that is an abbreviated description of the course of evo-
lution — not very complete, but a gallant attempt. But it pays no at-
tention to how evolution happened — to the mechanism. This is what
we want to get at now.

Item 1 of our agenda says that a major concern of modern evolu-
tionary biology is research on the mechanisms of evolution, particu-
larly as studied by experiment, both in the field — in nature and in

the laboratory.

Ford: First of all, I think it is necessary to clear our minds about

PANEL TWO: THE EVOLUTION OF LIFE • 113

this. Experiment in the field includes carefully controlled observa-
tions, which can provide just as good scientific data as experiment in
the laboratory. To take a simple instance: in estabUshing a new
colony of butterflies on a small island in the Isles of Scilly, the popula-
tion was taken from a large island, where its characteristics had re-
mained constant year after year. The spot distribution of the new
colony gradually changed, but the population from which it was taken
continued steady, acting as a control all the time. That is a perfectly
valid control. It is a question of observation rather than experiment,
in one sense.

I should like to raise two other points. To study evolution actually
going on in the field, it is necessary to pick situations in which natural
selection is operating rather powerfully, and those who have worked
on evolution taking place in wild populations have been careful to do
this.

The third point is that when we say we are studying evolution in
the field, we do not mean merely the spread of characters due to
changes in the environment but also actual changes in the characters
themselves. Let me give you an instance: Black moths have spread in
the industrial areas of Britain within living memory. To examine the
rate at which they have spread, how they spread, and what conditions
make them do so is very important. But a point many people miss
is that, in spreading, the black forms themselves have changed and
evolved, and, by examining them in the laboratory and breeding from
them, one can demonstrate that evolution. One can reproduce it ex-
perimentally by genetic methods in the laboratory and demonstrate its
occurrence in the field.

Huxley: I might add that the blackness is definitely adaptive and
that the black form has got blacker. A beautiful experiment in the
field is that of H. B. D. Kettlewell, who showed that birds picked off a
majority of those moths that did not match their surroundings. This
was an actual quantitative experiment.

Olson: I wonder if I might carry this discussion of experiment a
bit further. I am, of course, a non-experimental paleontologist among
geneticists. Axelrod and I are often at odds with interpretations of
experiments, since we derive data differently. But we are interested
in the mechanism of evolution in two ways. First, we are interested
in what the experimentalists find out and provide for our studies. We
feel, however, that our scale is much greater than theirs, and so we
sometimes question its total applicability. Second, since we work on
a greater scale, we think that we can see things that should be turned
over to the experimentalists for study, and in this way, by direct study

114 ' ISSUES IN EVOLUTION

of the fossil record, we can contribute to the understanding of mech-
anism. I believe we can broaden out further in this direction to the
benefit and understanding of all.

Huxley: I agree. All progress in any subject, such as biology, in-
volves straight description, comparative observation and analysis, and
experiment, with a constant interplay between them all.

Now we come to item 2 — the production of genetic variance, which,
of course, provides the raw material for all evolution and is enor-
mously amplified by sexual recombination, involving an exchange of
material between homologous gene sets. This is perhaps an inherent
property of strings of DNA and certainly must have started at an ex-
tremely early stage.

I think Stebbins wants to bring up James Thurber's famous question.

Stebbins: "Is sex necessary?" I think we should always quote from
eminent scientists when we can. Muller gave an answer to this question
about thirty years ago, when he pointed out that a continual shuffling
of genes, which results from sexual recombination, is necessary to gen-
erate the large number of gene combinations needed to produce a
new adaptation. We can also answer Darwin's question: Why do
flowers make so many efforts to insure or enforce cross-fertilization?
The selective value of cross-fertilization is the generation of new gene
combinations, since we now know that adaptiveness depends not just
on one or two genes but on an adaptive complex of many genes.

Wright: I should like to give an estimate here, bringing out the
extent to which recombination amplifies the variability due to muta-
tion. With only twelve loci and four alleles (ten compounds) in each,
there is the potentiality for 10^^ or a million million different geno-
types. One hundred loci with four alleles each is still a very modest
number, considering that mutations have been described at some five
hundred loci in the fly Drosophila melanogaster and that some twenty
afleles have been found at one of these loci. The three hundred muta-
tions in this case imply the potentiality for 10^''° different genotypes.
It has been estimated that there are less than 10^° elementary particles
in the universe out to the distance made visible by the Palomar tele-
scope. The number of potentiaHties — not, of course, actualities — from
one hundred loci, four alleles each, is thus that of the number of ele-
mentary particles in 10-° such universes.

Huxley: For many years biologists often said or implied that mu-
tation was the source of all evolutionary change. It is the original
basis, the raw material out of which the larger bricks are made; but in
the last twenty years we have seen that recombination of genes and
alleles is equally important, in a sense even more so, and just as essen-

PANEL TWO: THE EVOLUTION OF LIFE • 115

tial. And it is amazing how many of these possibilities can be reaUzed
even in one population.

Dobzhansky: Again we come back to the problem of sex. Steb-
bins asked: Is sex necessary? My answer would be that it is at least
desirable. Sexual recombination of gene stores in natural populations
produces a really tremendous amount of genetic variance, an amount
much greater than we dared to suppose even a few years ago. I think
one may be justified in making the rather extreme statement that, at
least in sexually reproducing higher organisms — taking Drosophila to
be a higher organism — suppression of the mutation process, if this
were possible, would probably have little effect on the evolutionary
plasticity of the population for some time to come.

Emerson: I should like to add one point about the evolution of
sex mechanisms. Most of our theory of evolution and most of our data
are based on the analysis of individual organisms. Many years ago — as
early as 1912, I believe — Huxley wrote a book about the individual;
and still most of our biological information is based on the individual.
These data on sex recombination mean that, besides the individual, we
are all included in higher-level organizations composed of relations be-
tween individuals. Sexual recombination and its importance in evolu-
tion necessitate an elementary population structure, so that higher
levels of organization involve supra-individual systems.

Huxley: Yes; and those are acted upon by selection. Stebbins'
earlier point that DNA can do nothing unless it is part of a system
with proteins is, in a way, obvious — so obvious that it is often neg-
lected. In the same way, an individual organism can't do anything
unless it is in an environment in a systematic relation with other or-
ganisms.

We say in point 2 of the agenda that sexual recombination must
have started at an extremely early stage. Is anybody willing to say how
early? Did it exist right from the beginning, or how soon did it ap-
pear?

Stebbins: In my pubHshed paper I agree with Ellsworth Dougherty,
one of my colleagues from Berkeley, that sex, or at least genetic
recombination, started with life itself. There is a question whether the
term "sex" should be used for the types of genetic recombination oc-
curring in viruses and bacteria; and the term "parasexual phenomena"
has been used for recombination in those organisms. When we realize
that these parasexual phenomena occur not only in viruses but in vari-
ous kinds of bacteria, the old idea that recombination did not appear
until after we had a full-fledged nucleus with its complement of elabo-
rately constructed chromosomes, as well as the various cytoplasmic
structures, must be abandoned. One very important point here is this:

116 ■ ISSUES IN EVOLUTION

if we say that genetic recombination is necessary to generate new
adaptive systems and then say that such highly adaptive and complex
systems as the cell of an amoeba, or a euglena, with its nucleus, chloro-
plasts, eyespots, flagella, etc., evolved without the aid of genetic re-
combination, we are contradicting ourselves. Even though we don't
know that genetic recombination exists in these one-celled organisms,
we must postulate its existence at the time they evolved.

Huxley: That is a very important point. It seems increasingly
probable that DNA is so important because, as Muller said yesterday,
it has the two properties of self-replication and mutation or self -varia-
tion. It also seems probable that, from the outset, DNA had this abil-
ity to recombine bits of itself with other homologous pieces. If so, then
this basis for more rapid evolution was present right from the be-
ginning.

This leads to point 3 : the self -replicating and self -varying properties
of DNA inevitably lead to natural selection. As Darwin himself said,
"natural selection" is a metaphorical term and thus has led to mis-
apprehension. No conscious action is involved in natural selection:
it is the name we give to the results of the differential survival and
reproduction of biological variants. Mutation and recombination pro-
vide the raw materials for evolutionary change. Natural selection is
the guiding or directive agency in that change. Other agencies, such
as so-called random "drift," sometimes lead to non-directive genetic
change in populations, which may, however, be combined with di-
rective change.

Wright: As Huxley brought out, the essence of Darwin's theory
of natural selection is that the interplay of random variation and selec-
tion leads step by step, through thousands of little steps, to results that
are utterly unthinkable as occurring at a single step. Modern genetics
fully supports this concept. I do not think any prominent geneticist
now would question the essential validity of Darwin's conception of
natural selection as the guiding principle in evolution. There is, how-
ever, a difference of opinion about the roles played by random varia-
bility at different levels. The genetic mechanism, as we know it now,
provides variability at two general levels: (1) that of mutation,
whether genie or chromosomal, and (2) that of recombination.

There is, first, what seems to me the oversimplified view that muta-
tions, classifiable as favorable or unfavorable, provide directly the
random variabiHty that is sifted by natural selection. In a population
that has been living under a constant set of conditions for a long time,
all the recurrent mutations would have been tested; fixed if favorable
and kept at very low frequencies if unfavorable. It is highly unlikely

PANEL TWO: THE EVOLUTION OF LIFE • 117

that a novel mutation will be favorable. Under these conditions, the
members of a species would be homozygous in the same sense in
nearly all loci, and recombination would play no appreciable role in
evolution. The possibility for evolution is thus decidedly limited.

The situation is more favorable in a species living in an environ-
ment that changes systematically from time to time. Recurrent muta-
tions that have been unfavorable may give better adaptation to new
conditions than did the old-type genes and may displace these fairly
rapidly. An example is the beautiful case described by Ford, in which
the environment changes from one in which light-colored moths are
protectively colored to one of soot-covered trees, in which light-colored
moths are very conspicuous to birds. Mutations that darken the color
approach fixation with great rapidity. Again, the recent rapid evolu-
tion of cyanide resistance by scale insects, of DDT resistance by flies,
and of penicillin resistance by bacteria under intensive efforts at con-
trol by these agents are examples that are beautiful only from the
evolutionary standpoint. The hypothesis that evolution proceeds from
the direct selection of favorable mutations is thus a possible view, but
only in conjunction with systematic changes in the environment. The
process is somewhat like a treadmill, with the species continually try-
ing to keep up with a continually deteriorating environment.

It seems unlikely, however, that the enormous amplification of vari-
ability by recombination plays no role. It has been abundantly demon-
strated that the effect of a combination of genes is, in general, very
far from being merely the sum of the effects assignable to the com-
ponent genes. This is especially the case with selective value itself as
a character, since the optimum grade of any quantitatively varying
character, even one that is evolving rapidly, usually differs httle from
the mean at any given time, with the consequence that each gene with
a positive effect tends to be favorable in combinations below the mean
and unfavorable in those above. In a population that is breeding at
random, favorable combinations of genes are broken up in the forma-
tion of the germ cells. There is delay in the case of linked genes, but
this is only momentary in terms of geological time. Selection can thus
operate effectively in this case only on the net effects of the separate
genes, not on the genotypes.

There seem to be only two general ways in which selection may be
based effectively in the genotype as a whole. One of these is by the
interpolation of many generations of asexual reproduction between
crosses, during which selection is between clones. Unfortunately, the
most advanced organisms — most insects and practically all verte-
brates — do not make use of this. Among these, the only possibility
seems to be through the more or less random differentiation of local

118 • ISSUES IN EVOLUTION

populations and selection among these by means of differential ex-
pansion and contraction. If the species is divided into a great many
largely, but not completely, isolated small communities, these will
inevitably drift apart in genetic constitution, partly under the in-
fluence of differences in local conditions and partly from random
processes. Such random changes occur whenever a population passes
through a bottleneck of small size. Moreover, fluctuations from the
prevailing trend of selection and of immigration have effects that may
be considered random. Under the above conditions, each community
will carry many slightly different alleles at each locus, and these will
be in different frequencies from those of other communities.

One consequence of selection toward intermediate values of quanti-
tatively varying characters in conjunction with pleiotropy (multiple
effects of each gene) is that there are a vast number of selective peaks
at different levels of selective value. This presents a serious obstacle
to selection under random mating, since the stronger the selection, the
more firmly the population is bound to a single selective peak — not, in
general, a high one. If, however, the species is subdivided as described,
Siose local communities that have more or less accidentally attained
relatively high selective peaks behave as population founts, and those
that are held at relatively low selective peaks behave as population
sinks. There is continual outflowing from the former and the forma-
tion of new founts by interaction. This process can go on indefinitely,
though largely invisible over considerable periods of time, since it
applies directly only to alleles that differ only slightly in effect (modi-
fiers, isoalleles). It should be added, however, that random differentia-
tion of local populations with respect to modifiers may prepare the
ground somewhere for acceptance of a major mutation that has been
kept at low frequency by unfavorable side effects.

From a broader standpoint, we may, I think, say that the most
favorable condition for evolution, including cultural as well as or-
ganic, is a suitable balance between inbreeding, whether in the literal
genetic or the figurative cultural sense, and cross-breeding, again
whether in the literal genetic sense or the figurative sense of cultural
diffusion and interaction.

Huxley: The environment of any species is by no means uniform.
It often varies seasonally, periodically, and so on, and this may result
in polymorphism, based on balanced systems of genes or alleles in the
population, one adapted to one set of environmental conditions and
the other to another. Dobzhansky has done very interesting work
on this.

Dobzhansky: That refers to a point I brought up earlier: the exist-
ence in natural populations of a tremendous store of potential vari-

PANEL TWO: THE EVOLUTION OF LIFE ■ 119

ability that can be released by recombination, by the Mendelian
process that is going on all the time.

Mayr: Our opinions have been so harmonious up to now that I
should like to introduce a slightly dissonant note. Wright said that
mutations are practically always injurious. This is certainly true of
the majority of the mutations studied by the geneticist. But the geneti-
cist does not work with a random sample of mutations; he picks out
those that are easy to work with because they are very conspicuous,
and these are nearly always injurious. There is a great deal of evidence
— and mounting evidence from the study of isoalleles — that many
other mutations have exceedingly slight effects and are not neces-
sarily harmful. They may be injurious or not, depending on the total
genetic background of that species or population or individual and
on the physical environment. If one thinks in terms of the DNA code,
one can easily imagine that some shifts in the code will have such a
slight effect on the chemical it produces that it will not be disruptive.
So I think that there is a good possibility that a considerable percentage
of mutations are not necessarily injurious.

Huxley: Isn't it possible that a great number of small mutations
gives the gene complex an additional elasticity — a kind of capacity for
regulating itself?

Mayr: Very definitely, I should say. The fact that, when a major
mutation occurs, its phenotypic expression can very rapidly be modi-
fied by selection indicates that all sorts of alleles having this general
effect are present in the gene pool.

Huxley: Ford just now gave a very good example of how a muta-
tion that is bad in some circumstances may be good in others. The
small mutations that made black moths blacker would originally have
been deleterious, but, once there was a black form under positive
selective pressure, they were advantageous.

Item 4 includes a very important point: the distinction between
change-inhibiting (stabilizing) and change-promoting (novelty-pro-
ducing) forms of selection. Of course, sex is involved in this and, in
non-sexual phases or forms, variance will be much reduced.

Emerson: I think there is a balance between the replicative func-
tion of genetic material and its function of change; and this conserva-
tive aspect produces a certain degree of stabilization. It is very im-
portant for the organism to hold on to the adaptive adjustments it
already has. Sometimes this stabilization operates for a very long
time, with a high order of genetic identity involved. Also, as the
organism becomes reasonably well adjusted to an environment, selec-
tion operates against change rather than for it. In some instances, the
sexual system has been eliminated by the organism because it pro-

120 • ISSUES IN EVOLUTION

duced possibly too much variation, which was too likely to be dele-
terious in an organism in a stable environment with a high order of
adaptation; so that stability runs along with change in the process of
evolution and produces this constancy that we see along with evolu-
tionary change.

Huxley: I am afraid that we must pass to the next item of point 4:
selection between individuals of the same sex and within and between
populations.

Nicholson: The distinction has already been made between stabil-
izing and change-promoting forms of selection. Another division,
which seems to me very meaningful, can be made following the the-
ories of natural selection put forward by Wallace and Darwin, which,
in fact, were not the same.

The simplest form of selection, as I see it, is that presented by
Wallace. The mechanism he described is just this: Animals or plants
in any environment are subject to considerable environmental change;
and during periods of great adversity those individuals that were not
good enough to survive would be destroyed. This process continuing,
more and more individuals of the temporarily unfit type would be
destroyed. With the return of more favorable conditions, only the best
forms would have survived and would exist under those favorable con-
ditions. Thus the mechanism here is the direct elimination of the unfit
— or, if you like, of the temporarily unfit. This is quite distinct from
Darwin's theory, in which such elimination is an indirect process.

Darwin's theory involves the idea of competition. Darwin held that
the fitter forms displace the others — the other forms that were previ-
ously perfectly fit — simply because they have a greater chance of
survival. As populations are necessarily limited, an increase in one
component of the population must necessarily lead to a decrease in
the other component. This is not an elimination of the unfit. It is a
displacement of normally completely fit individuals, which are unfit
only in the sense that they cannot compete successfully with their
more effective fellows. So there is a distinction between the type of
natural selection due to the direct elimination of the unfit and that due
to indirect elimination of individuals that are not quite so fit as the
new form.

Later I shall have more to say about the efficiency of the Darwinian
type of selection, which is much greater than the Wallacian type. But
there is a further point I should like to make now. For evolutionary
advance two things are required. One, of course, is the appearance
and the preservation of forms that have advantageous properties. The
other, equally important, is the disappearance of the preceding form.

PANEL TWO: THE EVOLUTION OF LIFE • 121

which was perfectly fit to go on living in the environment before the
new form appeared. This displacement, which in Darwinian selection
IS caused by competition, frees the gene pool from the influence of
these less well fitted or less potent forms, and the properties of the
population as a whole are improved as a result of this intraspecific
selection. Now, this should be contrasted with interspecific selection.
Competing species have no common gene pool. The displacement
takes place in exactly the same way— individuals of fitter species dis-
place individuals of inferior species, and do so completely, just as
happens within a species.

Huxley: Sometimes — not always.

Nicholson: Not always, it is true; but my point is that the disap-
pearance of the less fit form— the inferior species— has not in any
way improved the properties of the residual population— the superior
species — or contributed to its advancement. Evolutionary advance-
ment, then, requires intraspecific selection or intragroup selection
when the group of interbreeding individuals is smaller than the species.

Interspecific selection is a process that removes the dross of the
less fit forms of life from the earth— but does not contribute to bio-
logical advancement. That is left to selection within populations,
which have a very powerful mechanism for producing such advance-
ment.

Dobzhansky: I should like to emphasize, not how much we know
about selection, but how little we know. There is a great temptation,
especially when one reaches a certain age — which I have reached, as
have most of my colleagues on this panel— to speak about things as
really known and to represent them as cut and dried. Perhaps it is
better sometimes to talk about how little we know, how much we
must learn, and how necessary more research is. We have not properly
understood what biological fitness really is. For example, a form may
be fit in the short run, but this may injure its fitness in the long run, or
vice versa.

I think it is very useful to stress that here, as well as in many other
areas, more research is what we really need. We need more work, and
work on a broader front. We really need to know far more than we
do.

Ford: What I am going to say refers back to what Mayr was saying
just now of the way in which mutations having quite small effects may
really be useful. That is exactly why one can use polygenic characters
(that is, characters controlled by genes having small cumulative ef-
fects) for the study of evolutionary changes going on in the field, espe-
cially in isolation. With polygenic characters, one has a large amount
of continuous variation under genetic control. Further and this is

122 • ISSUES IN EVOLUTION

Mayr's point — the changes due to the substitutions at each locus are
so small that the organism can be adjusted by selection operating on
its total gene complex in relation to each of them. Consequently, you
can get a harmonious adjustment, in contrast with the very big changes
due to mutation of the major genes, which can infrequently be advan-
tageous because they produce such large effects that the organism
rarely has a chance to adjust to them. It is possible to get these adjust-
ments very much as Mayr said.

Axelrod: I fully agree about harmonious adjustment. But if we
follow climatic trends through long intervals of time, it seems to me we
can see the operation of another kind of selection, which we haven't
talked about very much. In paleobotany we call this "climatic selec-
tion." With a gradual change in climate, certain types, which earlier
were wholly fitted or harmonious, gradually disappear while others
survive because they are harmonious in more than one environment.
An exceptionally good example of this is found in the Mediterranean
regions of dry climate, where widespread extinctions, local at least,
occurred as summer-rain types disappeared but drought-resistant
types persisted. Yet earlier they were all together. Here, selection was
operating on a physiological background.

Wright: I should like to comment on a point Nicholson raised
about the difference between selection by the environment and selec-
tion by social interaction within the species. Under environmental
selection, one may equate the terms "reproductive value" and "selec-
tive value." This is not so with selection that depends on social inter-
actions. A type that flourishes at the direct expense of others of its
own species may continue to displace the latter, while lowering the
reproductive rate of the species perhaps to the point of collapse. The
closer the approach of the species to the peak in selective value, the
lower its reproductive value. Fitness becomes a highly ambiguous
term.

What is it that prevents species from succumbing to social parasit-
ism? There seems to be no solution in random-breeding populations, j
In a population divided into many local communities, which are '
largely, but not completely, isolated, intergroup selection among these,
governed to a large extent by their relative reproductive values, may
overcome selection pressures toward social parasitism.

Huxley: I don't think we need do more than read point 5, because i
it is really a statement of fact, whose impHcations can be brought out
later in the discussion. It reads as follows: "Biological evolution al-
ways shows a combination of continuity and discontinuity, a compro-
mise between stability and change, and an interplay between ran-

PANEL TWO: THE EVOLUTION OF LIFE ■ 123

domness and directional selection." Indeed, I think we can say that
all characters of all organisms represent compromises between several
biological needs or values.

I should like to go on now to point 6: the relations of develop-
mental — or, as we now call them, "epigenetic" — and physiological
processes to selection and evolution.

Prosser: We have been using the word "fitness" in a very general
and perhaps loose sense. I should like to put in a plea for an analysis
of fitness in terms of functional adaptiveness to environmental stresses.
No organisms live in a strictly constant environment. It is the essence
of living things that they show remarkable homeostasis or capacity for
self-maintenance in fluctuating environments and even in the face of
deleterious environmental factors. In general, developing organisms
are less capable of withstanding environmental variations than are ma-
ture organisms. This homeostatic capacity varies considerably, of
course, with the kind of organism.

In considering physiological factors in respect to natural selection,
one has to recognize two times at which the environment may affect
the individual organism. First, direct responses to environmental
changes permit a certain amount of homeostasis. Organisms may re-
spond in either of two ways. Either they may change with the en-
vironment and become equivalent to it in a given character, such as
the temperature of cold-blooded animals; or they may regulate their
internal state in response to a change in the environment. In general,
organisms that change with the environment — which we call "con-
formers" — tolerate a wider range of internal state and a narrower
range of environmental state than do organisms that are regulators.
Regulators tolerate a wider range of the environment but relatively
narrow ranges of internal variation. Both of these are short-term pat-
terns of response from which the organism returns directly to its orig-
inal state when the environment also reverts.

Then, in the changes that occur over a longer period of time —
larger fractions of the lifetime of an individual organism — one often
finds compensatory responses that tend toward stabilization. In this
state of acclimatization the organism has changed, since if the environ-
ment now returns to its original condition, the organism overshoots
or goes beyond its initial state.

We must recognize that natural selection is operating on the capac-
ity for such changes. Natural selection is homeostatis, operating over
many generations. Natural selection does not select a particular re-
sponse; rather, it selects the capacity for a given response.

Nature seems to operate with very large safety factors. In most of

124 • ISSUES IN EVOLUTION

the long-term compensatory responses, as well as in the direct reac-
tions, one finds multiple pathways for solving a given functional
problem. Usually there are feedback mechanisms of considerable
variety, which tend toward stabilization. I think if we analyze the
sum total of homeostatic responses of organisms in terms of natural
selection, we shall go a long way toward getting at the physiological
basis of fitness.

Huxley: This leads straight to the canalization of the processes of
development from the egg to the differentiated adult. Again, there
tend to be many kinds of feedback arrangements, canalizing deviations
back into the normal channel. Developing from an egg to a human
being or an ant or a frog or anything else is a terribly complicated
process. These very elaborate processes have to be blueprinted, laid
down, and selectively canaUzed. As a result, the course of develop-
ment that has been stabilized over millions of years influences the
future course of evolution. Each individual more or less has to go
along that path. This is the opposite of Haeckel's original "law of
recapitulation," Phylogeny does not determine ontogeny; put rather
crudely, ontogeny determines phylogeny — at least, it helps to deter-
mine it.

Mayr: The important point to stress here is that selection operates
on the phenotype, the final product of the interaction of all the differ-
ent genes. If the phenotype is particularly valuable and if a new mu-
tation occurs that — although otherwise adding to fitness — interferes
with the development of this phenotype, compensatory genes will be
selected which restore the original phenotype.

The same is true of interactions with the environment. Certain en-
vironmental shocks may affect the organism during development. The ,
total interacting gene complement must be prepared to produce the |
chemical substances needed to buffer the environmental shock, so
that development returns to its original pathway and the "normal"
phenotype is produced (canaHzation) .

I should like to say just one word about fitness. This term, unfortu-
nately, is used with several meanings. When biologists speak of fitness,
they do not mean it in the sense of an athlete who is fit. The strictly
operational definition of biological fitness given by R. A. Fisher is
the best I know. This states that if a gene maintains the same fre-
quency in the population from one generation to the next, it has a
fitness of one. If a gene, owing to its superior survival ability, in- j
creases its share in the gene pool of the species, its fitness is above one. '
When geneticists and evolutionists speak of fitness, they have this
meaning primarily in mind.

Emerson: I should like to point out that we are really saying that

PANEL TWO: THE EVOLUTION OF LIFE • 125

all organisms and all organismic systems have a time dimension. But
possibly we have not emphasized as much as we should that this is
not a linear time dimension from a cause to an effect but that the
effects influence repeated causes. These are the feedback systems.

Not only does feedback operate in this physiological system that
Prosser was just describing, but it operates back to the genetic system
likewise — from the adult to the embryo and developmental stages, as
well as the opposite. Thus we have an evolutionary "feedback" (I
don't like that word particularly, but then I know of nothing better).
Waddington has written very illuminatingly on this topic, showing this
feedback in evolutionary time. He demonstrated it experimentally,
and it is also obvious to us in terms of the course of evolution. This,
to me, is very important. It also gives us the basis for considering
adaptation to future conditions, especially if those conditions are re-
peated. The cause, for instance, can be influenced by the effect, pro-
vided that the cause is repeated. Not only that; we get the opportunity
to be adapted to a unique future condition. I shall not elaborate on
that at the present time.

Huxley: That leads on to point 7: Natural selection may lead to
side effects, which at the time are of no adaptive value but may later
provide the basis for adaptive changes: they are preadaptive or poten-
tially preadaptive.

Olson: We are just about winding up the discussion of selection
at this point. We have considered natural selection and random drift.
It seems to me important to emphasize another aspect supplying ma-
terial for selection, which fits here because it produces side effects.
This is the general area in which we can include events that are ran-
dom with respect to the adaptive value of the genotype of populations.
I refer to the simple matter of accident — for example, the effects of a
forest fire on a population, or perhaps something more general, where,
in terms of population structure and thd environment of existence
taken together, any adaptive genotypic superiority that might exist
is little, or not at all, expressed in the succeeding populations. This
sort of thing, it seems to me, is a necessary factor in interpreting very
rapid shifts in evolution and the apparently odd directions (from the
standpoint of adaptation) that are taken in evolution. This sort of
side effect, the impact of accidents and other factors producing non-
adaptive shifts, may cause very rapid changes and give completely
new shape to the course of evolution. I think this is an extremely im-
portant evolutionary factor.

Mayr: I should like to emphasize a point taken for granted by
geneticists but not fully understood by some evolutionists. In the early

126 ■ ISSUES IN EVOLUTION

days of genetics it was believed that every gene controls one character
and that every character is produced by one specific gene. Particu-
larly in higher organisms, however, genes do nothing of the kind.
The gene produces some kind of gene product — an enzyme or some
other and still unknown kind of protein — which is fed into the total
developmental stream and becomes part of the total developmental
system of the organism. It has been said — although this is surely an
exaggeration — that every gene contributes to every character of the
organism and that every character of the organism is affected by every
gene. Let us keep in mind that even a gene responsible for such an un-
important thing as, let us say, a slight aspect of pigment pattern of the
skin may simultaneously control longevity, aggressiveness, heat toler-
ance — all sorts of characters. This is one of the most important find-
ings of physiological genetics and has very far-reaching effects on the
interpretation of evolution. Therefore, let us never go back to the old
concept that a gene determines a character.

Huxley: Point 8 deals with the evolution of sex as an illustration
of evolutionary process.

Stebbins: I think we can focus several remarks made during the
last few sections onto the evolution of sex. In the first place, we can
ask this question: Why is it that in higher organisms sex seems so
essential and is never lost, whereas such organisms as fungi and bac-
teria get along for very long periods without sex or with only a very
small amount of genetic recombination?

For an answer we can go back to the point about compromise in
section 5 of the agenda. Some years ago, Kenneth Mather pointed
out that the genetic recombination system must establish a compro-
mise between two conflicting needs. One need is genetic insurance —
generating sexual combinations that at present may have no selective
value but may become essential in the future when the environment
changes. The other need is to generate the largest possible number
of individuals that are fit at the present time. And the balance — the
compromise between these needs — is likely to be very different in dif-
ferent organisms.

Take, for instance, a bacterial colony in which millions of individ-
uals are produced in one day, with the generation time a tiny fraction
of what it is in man. Here new genotypes can perhaps be generated
in large part by occasional mutations or even successions of mutations,
as in the adaptation of bacteria to streptomycin. In this case, sex is
perhaps of less selective value than in the slowly reproducing higher
animals. And in plants the larger, more slowly reproducing perennials
and woody plants usually have a high degree of cross-fertilization and

PANEL TWO: THE EVOLUTION OF LIFE ■ 127

genetic recombination through a high chromosome number, whereas
the weeds — the pioneers — usually have self-fertilization and some-
times asexual reproduction. This is associated with the fact that a
plant in a vacant and relatively uniform habitat is most successful if
it generates a large number of offspring similar to itself.

This seems related to Dobzhansky's remark that in the future we
shall have to think in somewhat different terms to find out more about
evolution. And in Evolution: The Modern Synthesis Huxley suggested
that we must think more and more of comparative evolution and com-
parative fitness of different organisms rather than in absolute terms.

Huxley: That is a very exciting statement about sex. Of course,
there are a great many other exciting statements to make about sex
— the way in which its existence has led on to such consequential char-
acters as sexual display and sexual selection, for instance — but we
really do not have the time to deal with them.

We are now on the second part of this enormous subject. We have
been discussing mechanism, and now we shall discuss the course, the
process, of evolution as shown in fossils and as deducible from animal
structure and behavior.

The single process of biological evolution involves at all times the
integration of three component subprocesses: first, diversification,
leading to branching and the formation of separate species and higher
groups; second, transformation, leading to detailed and general adapta-
tion, the greater efficiency of various functions, more advanced and
better-integrated organization, including the organization of behavior
and mind; third, stabilization, leading to the formation of stabilized
patterns of organization at all levels and to their often indefinite per-
sistence.

Axelrod: In the whole sequence of change seen in the geological
record, both animal and plant, these three phases — diversification,
then transformation, and, finally, stabilization — regularly appear. This
is especially well shown by the various major groups of vascular plants,
for which we now have records going back into the Cambrian. Each
successive group shows the major phases in change.

We do not know enough about change, and we need more fossils
so that we can analyze and interpret trends; but I think most of us
are in full agreement about the gradual change in time: increasing
diversification; then, gradual transformation, so new categories grad-
ually arise, first at smaller and then at higher levels; and these then
are stabilized and persist for long periods of time. Every major plant
phylum shown in the fossil record is still with us. The older phyla, of
course, are relict and not very conspicuous. Those that are dominant

128 ■ ISSUES IN EVOLUTION

— the flowering plants — cover the earth today in a diversity far greater
than the older groups.

Huxley: This is the point: that the paleontologist has to depend
on fossils. I am glad to hear that there are now more plant fossils than
there used to be and that these go back to the Cambrian. Zoologists,
on the whole, are more fortunate, and perhaps Olson could tell us
whether these processes can be followed in more detail in the animal
record.

Olson: I think it is important to recognize that, although the fossil
record itself is very incomplete, we can at one place or another follow
the operation through time of almost any process we wish. For ex-
ample, if we are interested in following species diversification in time,
we have to deal in very small units. This can be best done in the
Tertiary, with mammals, in the manner of Simpson and many others.
If we are interested in higher levels, we can take series of fossils, such
as that from the reptiles to the mammals, and follow a transition from
one class of vertebrates to another. This is so beautifully drawn that
at the present moment no one can adequately define a mammal on
the basis of the fossil record of the shift from reptiles. We are in the
center of gradual but profound change, and taxonomy is completely
confused. In one way, this is an ideal state. We really know something
if there is confusion in classification at such a level, because we have
crossed the boundary so perfectly that it is not possible to judge in
which major group particular animals belong. I speak here of verte-
brates; there is much to be done with invertebrates as well; but, so
far as fossils are concerned, these have been neglected at this confer-
ence. I

Just one more word: when we consider the fossil record and evolu- 1
tion, it is extremely important to realize that the record is highly
biased, as Simpson emphasizes in one of the Celebration papers. The
early record is very scant. Only as we come to modern times do we
really see a broad record in a variety of environmental classifications.
Earlier, it was ocean margins on both the land and sea sides of the
strand.

Huxley: Transitions from one major type of organization to an-
other are always gradual and always involve a great number of small
steps. G. R. de Beer has pointed this out in the evolution of the birds;
certain features of Archaeopteryx were reptilian, and others were def-
initely avian. I know it will be emphasized in the panel tomorrow that
the origin of man does not involve a single "missing link" but, rather,
many little links. This is a very important point.

Now we come to the statement that transformation leads to adapta-
tion and improvement. Personally, I like the word "improvement."

PANEL TWO: THE EVOLUTION OF LIFE • 129

Darwin used it characteristically in the Origin of Species when he said,
"Natural selection will inevitably lead to the improvement of most
species of organisms in relation to their conditions of life."

Ford: One of the very important things we have to recognize and
study is the way in which selection can adjust organisms to the effect
of single genes. For example, in butterfly mimicry, two distinct forms
may be controlled by a single major gene, and yet it has been possible
for selection to modify the gene complex, adjusting and gradually
evolving the mimetic characters within the effect of the major gene.
A combination of genetics and the study of organisms in their en-
vironments can show very well the breakdown of those adjustments.
It is very important to note that, although characters may be con-
trolled by major genes, they can be slowly and gradually evolved.

Huxley: And, as a result, there can be quite incredibly accurate
imitations of a nauseous form by an unprotected form; and when there
is no need for such close protection — when the nauseous form is not
present, for instance — the exactitude fades. Mimicry provides a beau-
tiful example of detailed adaptation.

Nicholson: It might be useful if I briefly described some recent
experiments in which natural selection took place before my eyes. I
did not set up the experiments for the investigation of natural selec-
tion, but to study population dynamics; but, fortunately, natural se-
lection occurred, and we have a detailed record.

I used the Australian sheep blowfly {Lucilia cuprina) in a series
of experiments. The populations were controlled by supplying the
adult insects with a small amount of meat juice each day. The flies
had to compete for this, and, in doing so, their numbers first increased
up to the point where the depletion of food by competition between
the flies prevented most of them from laying any eggs. Throughout
each experiment the number of offspring equaled the number of par-
ents, on the average, in spite of extreme osciflations in the size of such
populations from some 7,000 adults down to almost nil, in a regular
sequence.

When I made conditions more adverse in other cultures governed
in the same way by adult competition for food, the populations still
remained in being, and the same end result was obtained: the number
of offspring equaled the number of parents. There was a readjust-
ment. Competition relaxed to the point where its effect, plus the effect
of the adverse factors, prevented the production or survival of more
mature offspring than the number of parents, on the average.

In several cultures subjected to differing degrees of destruction,
each population fluctuated about different levels, but the mean pop-
ulation level remained constant during successive periods in each cul-

i

130 • ISSUES IN EVOLUTION

ture. In certain other cultures, natural selection of a very remarkable
kind took place, which caused the mean population levels to rise pro-
gressively.

I must point out that the unselected flies were able to produce far
more eggs than were necessary for survival of the species under the
conditions that were maintained. I found it possible to destroy 99.6
per cent of all immature adults each day, and the population still re-
mained in being. In spite of this, selection still took place to improve
Qgg production under the highly favorable conditions prevailing. It
proceeded very rapidly, and in about a year the properties of the flies
had improved enormously. An individual fly in the population re-
quired for egg production only a minute part of the amount of meat
juice needed by its ancestors at the beginning of the experiment. Thus
selection had taken place to improve a property that was already much
more than adequate to cope with the prevailing conditions. The im-
portant points are that this took place in a series of small steps and
that, although the mean population rose progressively, during any
moderate time interval the number of offspring approximately equaled
the number of parents. Thus, throughout the experiment, competr
tion had adjusted the population to the changing equilibrium levels

The important point from the standpoint of natural selection is
that automatic compensatory reaction adjusts the efl^iciency of selec-
tion at exactly the right point to preserve preferentially any better
form and allow it to multiply. As the better form multiplies and im-
proves the population, so the intensity of competition is increased
above the level that the preceding form could withstand. Consequently,
the previous form, perfectly well fitted, is displaced by increased com-
petition with the new form. This is the cause of the extreme efficiency
of the Darwinian type of natural selection.

Thus natural selection is not a process that depends on the appear-
ance of a new need before it can operate. If that were so, all organ-
isms would be in a very precarious state, because, as soon as the new
need arose, it would be necessary for the right type of mutation to
appear and to be selected swiftly. But with the type of reaction I de- ,
scribed, the population is held in being, even though environmental I
conditions may change very greatly. It can still adjust itself by re-
ducing in density and thus relaxing the intensity of competition. It
can remain stable under the less favorable conditions until some better
form happens to occur, which will then be selected.

Each time a better form appears, even though it is unnecessary
under the existing conditions, it will be selected. Such selection of
properties better than are immediately required provides populations
with resilience — if conditions become worse, the species is not de-

PANEL TWO: THE EVOLUTION OF LIFE • 131

pendent for survival upon the selection of improved properties but
can hang on — and also helps organisms spread into environments
that they were not previously competent to enter.

Huxley: Here you have definite improvement in relation to sev-
eral conditions of life and also what one might call "preadaptation."

Nicholson: After this same experiment had continued for another
year, selection led to the appearance in the population of a number
of individuals able to lay eggs without any meat juice at all — a re-
quirement that was essential to the species earlier.

Stebbins: This is a very interesting example of adaptation. I should
like to describe another example — a radical transformation that prob-
ably originated through the establishment of one gene with a major
effect rather than through a gradual change. This is the work of
Gajewski in Poland on the genetic difference between the common
purple columbine and a small white-flowered Asiatic form that lacks
the usual columbine spur. Now the purple columbine is pollinated
by bumblebees that have a proboscis just the length of the spur. The
spurless white Asiatic columbine is pollinated by flies and probably
by other indiscriminate insects. Gajewski found that the presence
or absence of spur is determined by a single gene. So we can recon-
struct a change in adaptation, triggered off by the appearance of the
gene that adapted the flower to the proboscis of the bee, with color
and other factors then coming in to complete the adaptation.

Mayr: The origin of new species or the multipHcation of species
is the first major step in evolutionary diversification. I shall not define
species, but I should like to point out their significance. We have been
talking about recombinations within a gene pool and the tremendous
genetic diversity within the total gene pool of a species, so that no
two individuals are ever quite the same. However, there is a limit
to the degree of difference among the genes that can be combined
and still lead to perfectly viable individuals. The fact that organic
nature is organized in the form of species is an insurance or protec-
tion of gene pools against their being polluted by unsuitable genes
from other pools.

Now how does a new species originate? The early naturalists dis-
covered long ago that the geographic ranges of closely related spe-
cies were often adjacent, and those of incipient species apparently
always so. Darwin's observation of this phenomenon on the Gala-
pagos Islands gave him the whole idea of the origin of species;
but it took eighty years or so before this empirical generalization of
the naturalists found an ultimate explanation by the population geneti-
cist. Up to that time, various alternate ideas of speciation were in-
voked, such as that individuals within a population became genetically

132 • ISSUES IN EVOLUTION

different as a consequence of ecological specialization. An alternate
mode of multiplication of species, which is particularly common to
plants, is through polyploidy. But in animals the essential process is
geographic speciation, for which the explanation was found by the
population geneticists.

Huxley: If Edgar Anderson were on this panel, he would object
to your saying "pollution" of gene pools by foreign genes. But such
introgression is a rather rare phenomenon in animals, and, from the
point of view of most animal species, it is pollution.

Dobzhansky: I have very little to add to what Mayr said, except
to stress again that in this field we have so much to learn. Just what
process brings about the formation of the isolating mechanisms that
separate species? We do not know this as well as we should. There
are two hypotheses. One of them is that the isolating mechanisms are
simply by-products of the accumulation of genetic differences. If you
become different, you become isolated. The other hypothesis is not
necessarily contradictory but, rather, complementary. It asserts that
reproductive isolation of species in nature is a product of natural se-
lection. Such isolation is built up by natural selection, which tends
to minimize the losses to the populations of both species that would
arise from gene exchange and recombination of species — foreign genes.

Another question is the extent of gene exchange between popula-
tions that is most favorable to the species. Recombination has to be
limited to a certain value — a certain frequency — which is optimal;
and the optimal amounts differ in different circumstances. We shall
have to find out by experiments, as well as by observations, to what
extent these two mechanisms — and perhaps others that are still undis-
covered — operate in nature.

Prosser: I shall emphasize another aspect of isolation. I do not
believe spatial separation is enough per se to cause speciation, and I
feel that there is a great need for identification of the isolating mecha-
nisms which do separate natural populations. Sometimes these also
operate for populations that are not at the specific level.

I feel that taxonomists have often been so busy describing species
in terms of key characters that they have paid too little attention to
the actual mechanisms of isolation. There are two categories of such
mechanisms.

The primary adaptations are those associated with physical factors
in the environment; if two populations are separated, let us say in a
geographic cline, they are usually limited by different environmental
factors. The identification of such isolating mechanisms can best be
made by applying stress tests to populations at the limits of the range.

The other type of isolating mechanism, which we might call sec-

PANEL TWO: THE EVOLUTION OF LIFE - 133

ondary, primarily concerns reproductive separation. These mecha-
nisms include many of the behavioral variations in animals. Fre-
quently, when climatic or physical changes cause the ranges of formerly
separated populations to overlap, the populations are then separated
by reproductive behavior rather than by environmental factors. I
think we have to separate these two kinds of isolation.

The study of physiological factors in isolation must proceed by
three steps. The first is the description of physiological variation in
natural populations. The second is to ascertain by acchmatization or
transplantation which variations are determined genetically and which
environmentally. Finally, the cellular mechanisms underlying the vari-
ations require elucidation.

Stebbins: I should like to disagree publicly with my good friend
Dobzhansky, with whom I have disagreed in private more than once
about the mechanisms of speciation. I do not think we have to con-
fine ourselves to the two alternatives he mentioned.

Dobzhansky: I expressly said they were not alternatives.

Stebbins: Well, to the two hypotheses, then. I should like to raise
another possibility, that reproductive isolation originates as the by-
product of certain specific types of natural selection and comes about
because of the nature of those types of natural selection.

The kind of hybrid behavior we find in animals is, in general, rather
different from that found in plant hybrids. That is, animal hybrids
tend to be inviable in early stages of development or to be sterile be-
cause of abortion of the gonads or mechanical disturbances of the
meiotic spindle and similar disturbances of meiosis; sterihty due to
the disharmony of the haploid products of meiosis is relatively un-
common. In plant hybrids, both effects occur; but much more often
the main bottleneck — the main limiting factor — is the result of meiosis,
the presence of disharmonious gene combinations due to the effects
of genetic segregation, which can be rectified by polyploidy. This is
probably because the epigenetic sequence of developmental processes
is much more complex in animals, and therefore selection for a dif-
ferent sequence of processes can much more quickly lead to dishar-
mony; just as with two well-adjusted Yale locks of different types
it is almost impossible to make one key open the other lock, but with
an old-fashioned door lock it is not at all hard to change the key to
get in someone else's room.

Huxley: The point is that organisms are excessively variable, and
we expect a great deal of diversity.

Mayr: As far as I am concerned, this is not a third alternative.
Stebbins says that the incidental changes occurring during isolation,
which will lead to eventual genetic isolation and to completed specia-

134 • ISSUES IN EVOLUTION

tion, are different in plants from those in animals. I entirely agree with
him about this difference. But this can be included in the first hy-
pothesis Dobzhansky mentioned, that is, that genetic changes are a
by-product of the general adaptive changes of isolated populations.

Dobzhansky: I agree with both Mayr and Stebbins.

Huxley: That's bad — we're all agreeing. However, I think every-
body does agree that some degree of isolation is a prerequisite for
the changes that later may lead to speciation.

I think Prosser was a little hard on the taxonomists when he said
they were so busy describing new species that they have no time to
think about their origin. Some taxonomists certainly have a hard time.
I think I am right in saying that 10,000 new species of insects alone
have to be described every year; and that is quite a job.

Prosser: In defense of my statement, I should like to see applied
function test as one criterion of speciation.

Huxley: You would then have to increase the number of taxono-
mists about tenfold and give them enough laboratory space and equip-
ment.

Emerson: As a systematist, I should like to have the physiologist
pay much more attention to taxonomic differences and evolution in
physiological investigations.

Huxley: Good. That's the advantage of getting people together.
Now we know what we want.

Olson: I think peculiar isolation was vaguely mentioned — that is,
temporal isolation with modification of time of the sort Axelrod men-
tioned earlier, never a split or two separate populations. It is going
through time and shifting;.

Huxley: You get both kinds.

Olson : I think this is extremely important.

Huxley: I think everybody agrees that types, once they are suc-
cessful, do tend to persist for a very long time. They usually are re-
duced in number by the emergence of new improved types, but they
may persist indefinitely. Stabilized systems — stable patterns of genetic
or physiological organization — are rather difficult to break out of. '
Advance of any sort has to be achieved by rather improbable break-
throughs from one stabilized pattern to another. This applies just as
much on the species level as it does on higher levels.

Mayr: The point I should like to make here is that species have J
another significance. Every single species is a new experiment in fill- "
ing some sort of niche in nature, because no two species are identical
in their ecological requirements. The majority of these different species
are merely variations on a theme, but occasionally a species will make

PANEL TWO: THE EVOLUTION OF LIFE ■ 135

a major "discovery" — for instance, the first fish that got out onto
land "discovered" the land niche and gave rise to the terrestrial verte-
brates and the first pseudosuchian reptile that "discovered" the air
niche and gave rise to the birds. So the species level is tremendously
important because only one out of thousands or tens of thousands
or hundreds of thousands of species is able to make this breakthrough
into a totally new type of ecological zone.

Now the question is: What permits a species to do this? Evolution
is exceedingly opportunistic, and the first step can be taken only if
that particular organism is preadapted for this change of its adaptive
or ecological zone. By "preadaptation" we mean that the structures
and physiological mechanisms of a species enable it to make the
switch. The fishes that gave rise to terrestrial vertebrates had fins that
were already like legs. They had an internal skeleton that prevented
their collapsing — as a jellyfish would — when they emerged onto land.
They had a respiratory system that permitted them to get oxygen di-
rectly from the air. They had any number of such preadaptations. And
this, I think, is the important point: if an organ has the potentiality
of two different functions, the addition of the second function to the
primary one opens up possibilities for such a breakthrough.

Huxley: These fish were also preadapted by fiving in an extremely
unpleasant ecological niche of little pools liable to dry up, so that they
had to get out onto land and walk about from one pond to another if
they were to survive.

Olson: Yes. The preadaptation was a matter of adaptation, which,
as Mayr said, was converted to another area, inefficiently at first but
later becoming effective.

A point I should like to raise — and a lot of people disagree with me
about this — is that I can't conceive of taking, as a point of break-
through (I don't like that word, but I shall use it because it is here), a
single species, such as the one that eventually gave rise to the mammals
from the therapsid reptiles. Many species in many lines were making
similar shifts.

Huxley: But only one got through.

Olson: No. Many or several got through, I think.

Mayr: I think this is a technical point. The various therapsid rep-
tiles that finally reached the mammalian level or zone go back to one
species.

Olson: Where?

Mayr: I don't care where, but —

Olson: Back in the amphibians or somewhere.

Mayr: Mammals, I think, are somewhat unfortunate as an example.
Birds show the one-point breakthrough more clearly.

136 ' ISSUES IN EVOLUTION

Olson: From your point, yes. I'll give you the birds.

Mayr: I think in many instances the major breakthrough was made
in only one line. In other cases, like the mammals, it was made in
several lines. This is a technical point. What is more important is the
preadaptation of an individual organ. People have always wondered
how fishes got lungs, for instance, or how any novel organ, like insect
wings, could have been acquired.

I think the development of lungs is now pretty well understood.
Certain fishes during the Devonian period lived in stagnant, fresh-
water swamps, where oxygen was so scant that respiration through
the skin and the gills no longer provided the necessary oxygen. Ap-
parently they came to the surface and gulped air, from which the
membranes of the digestive tract took up oxygen. When that stage
was reached, there was a tremendous selection pressure for developing
diverticles and enlarging this respiratory surface of the digestive tract.
As soon as the necessary gene combination providing such diverticles
appeared, selection pressure could push this tendency further and
further, and this led quite naturally to the development of lungs.

Any major evolutionary novelty that has been examined in detail
shows that the potential acquisition of a new function by an existing
structure was already present, and, as soon as conditions favored
structural modification, selection could take over.

Emerson: My point is a facetious one, but it seems apropos of
Mayr's description of the evolution of the lung. I once asked a profes-
sor of biology from the University of Tennessee how he handled the
problem of evolution. He said it was very simple, very simple indeed.
"I will tell my class that if this were any other state than the State of
Tennessee, we would speak of the evolution of the lung; but inasmuch
as we are in Tennessee, we will simply call it a diverticulum of the
alimentary tract."

Axelrod: Novelty in evolution does not necessarily involve a major
change in form. For example, I should call the desert and tundra
plants evolutionary novelties. These, I think, have evolved chiefly by
internal physiological change. Granting that some change of form has
accompanied the shift, the form changed as far back as the Miocene
period, or earlier, yet the physiological change accompanied the post-
Pleistocene appearance of these ecological zones.

Huxley: We are not necessarily talking of form but of any sort
of novelty.

Axelrod: The point is that these are wholly new regional environ-
ments that have been invaded recently, since the Pliocene.

Huxley: And where novel organisms have had to evolve; yes.

Prosser: One comment about novelty. In biochemical evolution

PANEL TWO: THE EVOLUTION OF LIFE ■ 137

we see a rather remarkable parallelism with the evolution of morpho-
logic novelties described by Mayr. As we said yesterday, the basic
classes of organic compounds — in fact, all the classes of biochemicals
— were established before there were organisms that we would call
such today. In the process of biochemical evolution, novelty has in-
volved the use of previously evolved classes of compounds for new
functions. Frequently this has been accompanied by minor changes
in the molecules, additions of side chains here or there; but the basic
compounds have not changed even with marked change in function.

In the area of animal nutrition, for instance, the so-called B vita-
mins function as coenzymes and are quite universal in all living or-
ganisms — certainly in all aerobic cells. A number of organisms, espe-
cially animals, have lost the capacity to synthesize many of these. Here
evolution involved loss of function and reUance on the environment
to supply the needed compounds. Similarly, the amino acids, which
are essential structural components of protoplasm, are substantially
the same from Protozoa to man. Here we have a pattern in which no
novelty has been introduced. Finally, the so-called fat-soluble vitamins
are modifications of classes of compounds that have other functions in
earlier forms. In the vertebrates, these have been modified consider-
ably, and they are required as vitamins only by the vertebrates. So I
think we have a distinct parallelism in biochemical evolution with
the development of morphological novelty.

Huxley: And then, of course, there is the case where the same old
compounds are used in different ways. I gather that either urea or uric
acid can be excreted, but birds excrete only uric acid because, if they
excreted urea, they could not have inclosed (cleidoic) eggs.

Prosser: It is interesting that the form of nitrogen excretion is
first correlated with ecological stresses; it is a very labile character.
However, the genetic limits within which it can vary may be very
different for different groups of animals.

Stebbins: This brings us back to something said at the very be-
ginning of this panel. When existing chemical substances are used for
new functions, we have evolution primarily in terms of reorganization.

Prosser: And loss of function.

Huxley: I think we should move on to point 13: whether we can
detect any general rules in long-term trends — one of the most im-
portant problems in the study of evolution.

Mayr: Studies of the geographic variation of species and of the
populations of a species throughout its entire range have shown that
a species is not the uniform typological entity that the early naturalists
thought. Every population of a species is adapted to its particular en-

138 • ISSUES IN EVOLUTION

vironment, as Prosser mentioned a few minutes ago. And as the en-
vironment shows regularities, becoming increasingly drier toward the
interior of a desert, let us say, or increasingly colder toward the north,
so does the variation of species living in such regions. Populations of
many species are adjusted to these climatic gradients and form what
Huxley has called "clines" — that is, character gradients. These regu-
larities have been formulated in a number of ecogeographic rules —
that the size of warm-blooded vertebrates tends to increase in cooler
climates, for instance, or that in more humid areas both vertebrates
and insects become darker, more heavily pigmented with melanin.

But in recent years the analysis of these rules has shown that, as
we stressed earher, all phenotypes are compromises among a variety
of conflicting selection pressures. As a result, there are many so-called
exceptions to such rules, where a new selection pressure takes over
and adjusts an organism or a local population in a different way.

Huxley: I doubt that anybody would disagree with that general
conclusion. CUnes constitute a very good example of the way selection
produces adaptive results related to graded characters in the environ-
ment. But much more important and exciting, of course, is the ques-
tion Can one detect any long-term trends at work in the huge time
scale of evolution?

Axelrod: In the plant world, these trends developed through time
as each successive group was replaced by another: first, the early
simple psilophytes; then the association of lycopods and seed ferns;
then conifers and cycadophytes; and, finally, flowering plants. We
find in this trend a gradual diversification and ramification, but each
successive group appears to have been able to cope with the oppor-
tunities offered it by both the physical and the biological world.

Huxley: What were the trends?

Axelrod: The trend has been toward increasing diversification in
meeting the environment with many kinds of adaptive types.

Huxley: Apart from diversification, what long-term, over-all
trends — increase in complexity, increase in reproductive efficiency,
and so on?

Olson: I think that, by "diversification," Axelrod was referring to
functional diversification within organisms. What has happened in
animal evolution is this specialization of functions within the verte-
brates (or other advanced organisms), so that each system is much
more specific in its functions. While special, however, the systems are
very highly integrated with each other. I think this is the most signifi-
cant point here. It has been an important key.

Huxley: Isn't it the evolution of a better-integrated, more complex
organization?

PANEL TWO: THE EVOLUTION OF LIFE ■ 139

Olson: Right.

Stebbins: With plants we can be even more specific and say that
the major trends on which our phyla, classes, or orders are based
represent more efficient ways of doing two things that land plants have
to do: ( 1 ) securing cross-fertilization of plants that are sedentary and
cannot move around and ( 2 ) securing more efficient methods of seed
dispersal. In each advancing group we see more complex and more
efficient ways of doing those two things.

Huxley: We have already touched on this point of the successful,
so-called dominant, types that rise, radiate, and become stabiHzed;
and I think we generally agree that by "progressive change" we mean
change in the direction of greater efficiency of over-all organization.

One point I should like to bring out is that we find a rise in the
level of organization, not only of body and structure and function, but
also of behavior; and this is accompanied by the emergence and in-
creasing organization of what one must call "mental properties." This
is to my mind the most extraordinary feature of biological evolution,
and it will be discussed in detail by Panel Four.

I shall try to summarize briefly some of the main points that have
been raised, and more or less agreed upon. We all accept the fact of
evolution. We all agree that some combination of mutation and re-
combination is the raw material for change and that natural selection
is the main directive or directional principle and that natural selection
is not conscious — it is the result of the differential survival of variants
through the generations. This means that biologists no longer need —
and no longer can — think in terms of Lamarckism, or of so-called
orthogenetic evolution — some inner urge, some elan vital that makes
organisms evolve as they do.

Selection acts on populations rather than on organisms, and it acts
through the phenotype of the population — in R. A. Fisher's epigram-
matic phrase, "Natural selection is a mechanism for generating an ex-
ceedingly high degree of improbability." It produces branching; it
produces increasing adaptation, improvement, progress, or whatever
you like to call it; and it produces horizonal persistence of branches,
or stabilization. As a result, selection operates not only between indi-
viduals or populations but also, in the long run, between major groups
— classes or even phyla. This results in the succession of so-called
dominant types. I think that would summarize most of our main points.

Of course, it is obvious that, although there has been a great deal of
agreement among us, there is also a certain amount of disagreement
about what we know, and a great deal of agreement that there is a lot
we do not know. So I should like each member of the panel to say

140 • ISSUES IN EVOLUTION

where in his field he thinks that ignorance is greatest and most likely
to be filled up by further research in the next generation or so.

Axelrod: We need more comparative surveys of major alliances
of plants in terms of the environment. Such studies were made some
time ago by J. W. Bews in Africa and E. C. Andrews in Australia and
more recently by J. S. Beard in tropical America; but, in general,
these are almost the only researches in this area — really an ecological
deployment in the adaptive radiation of plants — which has scarcely
been touched. The age and spatial relations of the different climatic
zones are pretty well known, and, by turning to studies of natural alli-
ances that are deploying through time and space, we can see the ways
in which these have responded to the environment through time.

Finally, one small point: the recent work in pollen analysis opens up
a tremendous vista in research on rates of evolution, not only in moun-
tainous regions where sediments are preserved but also on volcanic
islands. Here we can look for pollen preserved in old soil profiles, be-
tween lava flows, and also in fine volcanic ash; and what this shows
should be eye-opening.

Dobzhansky: I can see so many fields in which work is necessary
that I cannot even begin to answer the question. Since I have only
sixty seconds or so, I shall choose one point: the genetic population
structure in different organisms. This is a tremendous problem, which
has to be studied both from the standpoint of the theory of evolution
and from the somewhat narrower standpoint of genetics. The problem
has been brought to our attention in recent years, particularly in con-
nection with genetic damage by radiation. Our knowledge of the basic
rules governing the genetic structure of populations is really surpris-
ingly slight, and it is urgent to know more.

Huxley: You mean that there is a great deal to be discovered by
determining the differences of genetic systems and organization among
the different types?

Dobzhansky: I mean that the genetic structure of populations
probably differs in different organisms.

Ford: I have two or three projects that I consider essential. Many
of our really important conclusions are based, not on defective evi-
dence, but on rather good evidence drawn from too small a number of
different species or groups. We want much more analysis of the genetic
structure of populations. We want more experiments in greater detail
on the evolution of the effects of genes and on the ways in which the
effects of major genes can be modified. This is particularly relevant
to things like evolution of dominance and especially the evolution of
heterozygous advantage in genetic polymorphism, because in recent

PANEL TWO: THE EVOLUTION OF LIFE ■ 141

years there have been some attempts to suggest that this phenomenon
is rather rare or unusual. Finally, a point I should have liked to de-
velop much more is that we need far more estimates of the selective
advantage of genes in nature. When R. A. Fisher wrote The Genetical
Theory of Natural Selection in 1930, he was considering selective ad-
vantages in nature up to about 1 per cent. We are now finding that
selective advantages of 40 or 60 per cent are common in nature. This
needs much further study and requires quite a lot of rethinking.

Mayr: I have one point from my own field and it is pretty much in
line with what everyone else has said. Most of our knowledge of
speciation is based on a few species of birds, butterflies, and moths,
and we need to know a great deal about the lower types of animals,
particularly those that are specialized ecologically or in their mode
of reproduction.

There are one or two other points, from other fields, which I am
interested in as an innocent bystander. Paleontologists have described
many lines that remained unchanged, completely stabilized, for 120,-
000,000 to 140,000,000 years, and then suddenly broke out during a
new evolutionary outburst. Just what can cause such loosening-up of
tightly knit systems is something I think we should work out if we can.

A second point is that we find so many cases of extreme sensitivity
of natural selection, doing the most incredible and impossible things;
and yet the whole pathway of evolution is strewn left and right with
the bodies of extinct types. The frequency of extinction is a great
puzzle to me. Far too little attention has been paid to the factors re-
sponsible for this failure and breakdown of natural selection.

A third point concerns biochemical novelties. The major ones seem
to have been with us for quite some time, perhaps from the beginning.
But what about the role of the minor novelties? I should like to know
to what extent they may be involved in these sudden breakthroughs of
new major groups.

Emerson: I am going to make my statement extremely brief. I
would say that we need much more precise information on the evolu-
tionary time dimension within all the biological sciences — behavior
and development and so on. Second, I would say there is a great ques-
tion of the precise role that is involved in conflicts, incompatibility, co-
existence, and co-operation, both within and between species.

Huxley: Unfortunately, we did not have time to discuss that im-
portant point.

Nicholson: I think that there is a very great need to give much
more attention to population dynamics in relation to natural selection.
Darwin's theory of natural selection had two parts. The first of these
was the appearance and the preservation of superior types of indi-

142 ' ISSUES IN EVOLUTION

viduals, and that, of course, is the provmce of modern genetics. The
other part concerned the removal of the earlier form, which was not;!
so fit as the new form — not the disappearance of unfit forms but re- ;
placement of previously fit forms. For a long time now, attention has i
been given alrnost entirely to that first part. I have great admiration for
the work of the geneticists and for all the advances they have made;
but I feel that this has caused a very one-sided development of evolu-
tionary theory, which is coming to be regarded as almost a branch of
genetics. I believe that if the population dynamics aspect of evolu-
tionary theory were properly developed, it would be found to be
equally important and probably equally complex. I think that that
has been demonstrated this morning. Population dynamics provides
a system that holds populations in a state of stability and allows selec-
tion to proceed in spite of its disturbing influence upon populations.

One further point is the multitude of different systems of population
regulation. We know a little about some of these now, but we do not
yet know very much. I am sure that when we know more about these
systems, we shall find that they have influences upon natural selection
even more important than those I have already indicated.

Huxley: I am glad you raised this point. It is clear that we are
moving toward increased study of population growth and dynamics
from the genetic angle as well as from other angles.

Olson: The important word is "paleoecology": the placing of the
changing populations in their ancient settings in such a way that the
movement of whole systems through time could be studied. This
should be a major area of study in paleontology in the future. Also,
I feel that this panel demonstrates the need for better education of
paleontologists as biologists, and — amen — vice versa.

Prosser: First, I should like to see increased use of functional cri-
teria in the description of natural populations and in identification of
isolating mechanisms.

Second, I want to learn how environmental stresses operate to bring
about changes in the phenotype. We have evidence that temperature,
saUnity, oxygen, partial pressure, and the like can bring about bio-
chemical changes and that these changes are essentially enzyme induc-
tions. We beheve, from work on micro-organisms, that enzyme induc-
tion involves the production of new template RNA. Yesterday we
talked a great deal about DNA. We know RNA is produced under the
influence of DNA. What I am suggesting is that we have here the
possibility of feedback from a physical factor in the environment ulti-
mately to the nucleotides. This is somatic and has no direct effect on
the genotype; but it provides the material on which natural selection
operates. There is a real opportunity and a real challenge for the next

PANEL TWO: THE EVOLUTION OF LIFE • 143

generation to understand what I would call the "molecular basis" of
natural selection.

Stebbins: I should like to begin where Prosser left off, and I think
the facts he developed are most important. Now yesterday we saw on
this platform a beautifully colored model of DNA. We can go down-
town and find beautifully dressed models of a different sort. We know
the second type of model originated from a fertilized egg containing
forty-six strings of DNA. When we find out how those forty-six strings
of DNA effected all the differentiation of cells, tissues, and organs, all
the forward steps and feedbacks, eventually ending in this beautiful
form we all admire, then we shall be better able to argue about the
selective basis of adaptations, the emergence of novelties, or any other
type of change.

Wright: I think anything that I would say would be an anticlimax.
Moreover, the points that I had in mind have already been mentioned
in one form or another.

Huxley: Too bad your name begins with a W. But don't you want
to say anything?

Wright: I may say, then, that, with respect to the stage in the evo-
lutionary process with which I have been concerned — the lowest — I
should go along with Dobzhansky. We need much more detailed stud-
ies of population structure of species in nature and many more inten-
sive studies of the genetics of differences among local communities.

Huxley: Also, I take it, you entirely agree with Stebbins.

Wright: I agree with everybody.

Huxley: I think if Charles Darwin had been alive for this panel, he
would have been bewildered by the many new problems, new terms,
and new ideas that have come up. But he would also have been very
excited. I am sure that if we were to assemble one hundred years hence,
we should be equally excited and equally bewildered; but we certainly
have a wonderful field full of problems for biologists to follow up.

PANEL THREE
MAN AS AN ORGANISM

Chairmen: George Gaylord Simpson and F. Clark Howell
Panelists. Marston Bates; Cesare Emiliani; A. Irving Hallowell;
L. S. B. Leakey; Bernhard Rensch; C. H. Waddington

Topics for Discussion

I. Introduction: the status of man in the biological world

A. The systematics of man

B. The evolutionary status of man
II. The course of human evolution

A. Early hominoids

1 . The primate background as a basis for human origins

2. Early (especially Miocene) hominoids

3. Basic adaptations (limbs and tail; question of brachiation;
dentition; habitat and diet)

B. Early hominids

1 . The australopithecines

2. Adaptations at this level (posture; anterior tooth reduction
in relation to hands and brain; tool-making; habitat and
diet)

C. Hominines

1. Fossil hominines

2. Pleistocene time scale and antiquity of fossil men

3 . Ecology of primitive man

4. Effects of Pleistocene glaciation

5. Rates of human evolution (changes in rates; environmental
pressures; population size and structure)

6. Evolution of the brain (qualitative and quantitative; psy-
chological reconditioning; instinct, learning, and teaching)

7. Local differentiation and over-all progression (subspecies;
present unity and diversity)

III. The factors of human evolution

145

146 ' ISSUES IN EVOLUTION

A. Genetic factors (mutation, recombination, selection)

B. Ecological factors (adaptive roles; choice and modification of
environment)

C. Developmental factors (Isman"pedomorphic"?)

D. Trends

1. Progressive changes; kinds and degrees of improvement

2. Interaction of somatic and cultural evolution

3. Transmission and receiving in genetics and in culture

4. Development of value systems

E. Present biological status and future of man

1. Somatic

2. Cultural

The Discussion

Simpson: I think a chairman should be a benevolent poHceman
rather than a participant. Nevertheless, I have been persuaded to start
the discussion with a brief statement about the systematics of man.
When one is going to discuss any subject, it is always well to explain
what one is talking about; so I think we should say a Httle more ex-
pHcitly what man is in the sense of his zoological classification. This
will also introduce some of the terms to be used in the subsequent dis-
cussion.

Although man is certainly a unique and very extraordinary animal,
he is an animal. From the zoological point of view, man must be
classified just as is any other animal, and he fits perfectly well into the
natural system of organisms. It is simply a matter of defining his place
in this system.

Living man, of course, belongs to the single species sapiens of the
genus Homo. This genus belongs to the subfamily Homininae; so
hominines are the close relatives of Homo sapiens — fossil men in the
strictest sense, going back to Pithecanthropus and including a great
many other forms such as Neanderthal man as well as fossil Homo
sapiens. The Homininae form one subfamily of the family Hominidae;
the other hominid subfamily is the Australopithecinae.

A still broader group to which man belongs is the superfamily
Hominoidea; hominoids include not only the hominids (man and

the australopithecines) but still more distant relatives, the Pongidae

all the living great apes and a large array of fossil forms, some of
which lived before the Hominidae, strictly speaking, had appeared.
The superfamily Hominoidea is often put with the monkeys into a
group Anthropoidea.

To come down to still broader classifications, the order Primates in-

PANEL THREE: MAN AS AN ORGANISM • 147

eludes not only man, apes, and monkeys but also the premonkeys or
prosimians — the lemurs, tarsiers, and so on. Primates, of course, forms
an order of the class Mammalia. So much for the systematics of man.

I shall ask Waddington to lead off with a brief statement about the
evolutionary status of man, bringing out some of the characteristics
that make man unique and that are important in man as an organism.

Waddington: Before we go into the nature of man as seen by the
anthropologists, we should see how he compares with the rest of the
animal world from the point of view of those who are primarily in-
terested in non-human organisms; and particularly we ought to see
how man looks in relation to the evolutionary processes of that sub-
human world.

Evolution in the animal world takes place by the operation of four
major factors; or we may say that there are four main aspects of the
evolutionary system. ( 1 ) One is what we might call in a broad sense
the genetic system. (2) Then we have a set of processes that I refer to
as the epigenetic system: these are all the processes that transform the
fertilized egg into the adult organism. (3) What I call the exploitive
system concerns the way in which the animal utilizes its environmental
possibilities: all animals have around them much wider possibilities
of life than they are able or willing to utilize, and they do, in fact, live
in only one of the possible ways they might have chosen. (4) Finally,
we have the fourth system, natural selection.

How does man compare with other animals in these respects? The
genetic system comprises all the processes that, first, give rise to varia-
tion and, second, allow this variation to be transmitted from one gen-
eration to the next. It includes the mutation of the genes, the recombi-
nation of genes, and the systems for passing on genes from one genera-
tion to its offspring. Systems for transmitting variations are quite
varied in the lower organisms. Viruses, bacteria, etc. use all sorts of
mechanisms to effect the recombination and transmission of hereditary
determinants. But all higher organisms rely on one particular mech-
anism, the sexual system, which involves a diploid stage in the life-
cycle combined with reproduction by means of haploid gametes. Any
deviations that we find in higher organisms can be regarded as de-
generations from this system rather than advances over it. Man, of
course, falls into line with other higher organisms in his reliance on
the sexual system. The previous panel asked whether sex is necessary.
I think the fungi would say No; but for man — and I don't know
whether you would consider this to his advantage or not — we should
have to say Yes. At any rate, man's genetic system is much the same
as that of any other higher organism.

148 • ISSUES IN EVOLUTION

In the epigenetic system, also, I think that man follows the same
kind of processes as do most other higher animals. His development,
however, takes a very long time, and this lengthy period between the
fertilization of the egg and the attainment of the adult state gives man
more opportunity than most animals to carry out developmental modi-
fications in response to environmental stresses and thus to adapt him-
self to the environment to a greater extent.

I think it is very clear that in the exploitive system man has made
enormous advances over any subhuman animal type. Man is the most
widespread of all highly evolved species, and he can cope with a greater
range of environmental possibilities. In the animal kingdom as a whole,
the higher and more evolved animals tend to be able to exploit more
complicated relations between elementary situations in their environ-
ment. Progress in evolution is not so much a matter of exploiting
simple situations more fully as of exploiting interrelations. It is this
trend that man carries much further than his evolutionary ancestors,
first, by his use of tools, which enables him to modify his environment
much more than any other animal can, and, second, by his use of in- i
telligent conceptual thought, which is a method of exploring the rela- I
tions between things in the environment and making use of those rela-
tions.

Man is, like other organisms, subject to natural selection. In fact,
the occurrence of natural selection is in some ways a truism: if certain
organisms reproduce faster than others, they will have more offspring;
and man is subject to that law like any other living creature. Human
activities have a profound influence in determining which types of
human beings will actually leave most offspring. Man himself plays a
great part in deciding which types will be favored by natural selection
and which disfavored. Yet, however much man alters the criteria of
biological fitness, he will still be subject to the general process of nat-
ural selection and so fall into the same category as evolving subhuman
organisms.

As a purely biological system, then, man's main advance over sub-
human organisms is the greater development of his exploitive system.

But, before we end this comparison of man with other organisms as
evolving systems, there is another point to be made. Man has acquired
what amounts to a totally new evolutionary system. It is a truism that
the major characteristics of man include conceptual thought and the
communication of information by language, writing, and the like. In
this evolutionary context the important point is that conceptual thought
and language constitute, in effect, a new way of transmitting informa-
tion from one generation to the next. This cultural inheritance does
the same sort of thing for man that in the subhuman world is done by ,

PANEL THREE: MAN AS AN ORGANISM ■ 149

the genetic system, which transmits its "information" from generation
to generation in the form of a DNA chain. Man can similarly transmit
information in the form of actual letters on the page. The analogy
often made between the DNA chain and writing can be used in reverse;
and language can function as we are used to thinking that DNA does.

This means that, besides his biological system, man has a completely
new "genetic" system dependent on cultural transmission. No other
animal has developed such a system to anything like the same degree
of perfection, although you find traces of it in the subhuman world, as
any evolutionary theory would lead you to expect. The human species
has developed this system to such a degree that many people — myself
among them — think the greater part of the most important "informa-
tion" transmitted from one generation to the next is passed on by social
transmission.

With a new system for transmitting information between genera-
tions, one is bound to get a new system of evolution based on it. At
this point I think it is necessary simply to mention that man differs
from all other animals in this way. We shall pursue this point further
at a later stage in the discussion.

Simpson: We shall now take up human evolution and human ori-
gins chronologically and, in zoological fashion, start with the more
distant relatives and work down to modern man. This seems the very
core of the subject of man as an organism, especially in a conference
on evolution. One of the best ways of understanding any organism is
to understand its history; and this is human history, especially in a
biological sense.

We begin by taking for granted by far the greatest amount of or-
ganic evolution as having already occurred. We assume that the verte-
brates, the mammals, and the primates have arisen, and we shall dis-
cuss how man happened to arise among the primates. How did it
happen that our ancestors were primates and not, for instance, kanga-
roos?

Howell: It is necessary to take as given much of the data that
Simpson subsumed under the head of "systematics." We shall not
have time to discuss the monkey, prosimian, or pre-primate, arboreal,
primitive stages bearing on the ancestry of hominoids and, in particu-
lar, on the ancestry of hominids.

Comparative anatomical data shed considerable light on human
evolution and appreciably broadened our concept of man. Many
characteristics sometimes thought of as distinctively human are actu-
ally shared with other animals, including those that made man a
hominoid, or a member of the larger category Anthropoidea, or a

150 • ISSUES IN EVOLUTION

primate. Such characters as binocular vision, stereoscopic vision, re-
duction of the olfactory apparatus, the pattern of dental replacement,
and number of teeth relate man to other members of the primate order.
It is necessary to keep such facts in mind to avoid regarding as spe-
cifically human certain general characteristics relating man to many
other organisms. Our program is roughly arranged so that from the
more general we proceed gradually in a systematic fashion toward the
more specific — or, if you wish, the more human — and the more
recent.

Bates: You didn't explain why we didn't come from kangaroos.

Howell: I should ask Simpson that, since he has the greatest ex-
perience with the paleontological record.

Simpson: The early primates were just the sort of animal from
which a curious creature like man could arise. Kangaroos simply do
not provide the basis for the development of a creature like man. If an
equally intelligent organism arose among the kangaroos — which is
most unlikely — it certainly would not have the same characteristics at
all. Can anyone else add to this statement?

Waddington: Doesn't this matter of why we didn't evolve from
kangaroos involve some important aspects over and above the purely
anatomical considerations? Supposing there had been in the kangaroos
a mutation producing more intelligence or greater ability to communi-
cate, would not the natural selective advantage of such a mutation de-
pend to a large extent on the organization of the animals into social
groups? The possibility of conceptual thinking and of the transmis-
sion of thought in the way man transmits it seems to depend not only
on an anatomical basis but also on what you might call a social-
organization basis.

Bates: From this point of view the other group of mammals from
which we might have arisen would be the canines, which have a some-
what similar social organization. But there we should have the handi-
cap of being a canine without hands.

Simpson: Didn't Clarence Day write a book. This Simian World,
in which he speculated on what the world would be like if man had
originated from cats?

Hallowell: Although we have considerable information about
the social Ufe of non-hominoid primates in their natural state, it is still
a very small sample. But from even these limited data one might say
that, since practically all members of the primate order are social ani-
mals, almost all the anatomical changes involved in human evolution
have occurred in species that were social in their manner of living
from very far back. This is why I think Waddington's point is so vitaL

PANEL THREE: MAN AS AN ORGANISM • 151

Rensch: The prolongation of postnatal growth in higher primates
is also of great importance.

Here we touch a fascinating question, of equal interest to biologists,
philosophers, and even theologians: how far the origin of man may
be considered an accidental or an inevitable process. In all species of
higher animals each individual is unique because of its special set of
genes and its specific types of proteins. Spontaneous mutations are un-
directed, and the conditions of selection occur at random. Hence each
phylogenetic step is a unique, unpredictable event.

In evolution as a whole, however, phylogeny is not always so un-
predictable but, on the contrary, is governed by many laws. The
phylogeny of mammals, for instance, has been guided by the following
laws or rules: the law of steady adaptation in consequence of steady
mutation and selection; the biogenetical rule; Cope's rule of successive
increase of body size; Cope's "law of the unspecialized"; the rule of
irreversibility; the rule of progressive brain size and special progress
of the isocortex; Bergmann's, Allen's, Glazer's, and other climatic
rules; etc.

It is also possible to show that evolutionary progress was not acci-
dental but was forced by the interaction of the law of steady mutation
and selection, the law of successive improvement, and the law of the
non-specialized. Thus animals with more rational structures and func-
tions arose.

Man could originate only from homoiothermic animals, which alone
had a metabolism high enough that human performance and achieve-
ment would be possible. And among mammals the monkeys in par-
ticular show many characters favorable for the origin of man.

Hence I see the development of higher types of mammals and, to
some extent, of a being like man as necessitated.

Simpson: I can understand the rise of man being governed by law
without being quite inevitable; but this is certainly a very interesting
concept.

Hallowell: We might say, then, that the social life and social
organization of the prehuman primates would represent a stage pre-
adaptive to man?

Rensch: Yes; that is what I wished to say.

Hallowell: That is what I wished to clarify.

Simpson: Let us now consider the actual fossil evidence of early
hominoids. This panel is fortunate in the presence of Leakey, who has
made many essential discoveries in this field.

Leakey: We have very few specimens of fossil primates, compared
with almost every other order of mammals. While it is not easy to give

152 ■ ISSUES IN EVOLUTION

a positive explanation for this relative lack of specimens, I will advance
a hypothesis. It seems likely that most primate genera inhabited forest
or woodland or open country not very close to water. In such circum-
stances, when they died, their bones would not normally be fossiUzed.
Generally speaking, fossilization occurs only with animals living in
fairly open country not very far from lakes, streams, or rivers into
which their bones are washed soon after death and mineralized by
water carrying minerals in solution.*

Although the total number of known fossil primates remains small,
there has been a great increase in the number of specimens within
certain groups, particularly Proconsul and Limnopithecus, whose way
of life made the fossilization of their bones more likely. We know from
studies of the contemporary fauna that these groups lived out in open
grassland near a lake shore.

The evidence today indicates that during the Miocene and Pliocene
the Hominoidea were diversifying greatly and included a large number
of genera*. Dryopithecus, for instance, is found both in Europe and in
the Siwalik Hills of India; and in India we have a secondary center of
evolution with a whole series of very interesting fossil Hominoidea:
Bramapithecus, Ramapithecus, Sivapithecus, and many others. We
have too little data to be certain of their exact relation to man or to
other members of the Hominoidea, and we need a much more intensive
search for fossil primate remains. -Most of the known genera seem to
have been forest dwellers closely allied to the great apes or Pongidae.*
For the moment, we also include Proconsul in the Pongidae, but it
becomes increasingly possible that we shall have to set up a separate
family, Proconsulidae, to distinguish him from the Pongidae in the
strictest sense.

♦From our study of the limb bones of Proconsul and of the associated
fauna, we have increasing evidence that Proconsul lived out in the
open and had arms and legs of relatively equal length, making him a
normal quadruped.* Personally, I doubt very much that man ever went
through a stage with short legs and very long arms, such as we find in
the great apes today. I believe, rather, we shall eventually find that man
arose directly from a quadrupedal primate similar to Proconsul and
acquired an upright stance without developing long arms.

Simpson: You vote No, then, on this question of brachiation. Does
anyone wish to vote Yes or to add to the evidence for No?

Hov^ell: I think the evidence favors most of Leakey's conclusions,
and many of us would agree with him. With the brachiation problem
it is necessary to specify very clearly what we are talking about.
Brachiation, of course, means moving by means of climbing and swing-
ing with the arms — an overhead progression through the trees, like

PANEL THREE: MAN AS AN ORGANISM • 153

a trapeze artist. The word was introduced at the end of the last
century by Keith, who observed that gibbons, the smallest of the
living hominoids, moved about in this way in the forests of Southeast
Asia. In one respect it is unfortunate that he chose the gibbon, which
is the extreme arm-swinger and probably was the first hominoid to di-
verge completely and become adapted to a very special way of life.
Orangs, of course, are similar arboreal arm-swingers but are heavy
and terribly slow. Gorillas are arboreal cHmbers that have become
large and spend most of their time on the ground; but young gorillas
or the lighter-bodied chimpanzees move through the trees in a very char-
acteristic fashion. Their use of arms in overhead climbing movements is,
in a way, very human, very similar to children playing in trees — an-
other way of saying that man is apelike in his ways of behaving. But
whether man went through a brachiating stage has been obscured by
the fact that the living apes are very speciaUzed, just as living man is
specialized in some respects.

Many of us believe that the hominoid forms living in the Miocene
were not specialized in the same sense that the derivative forms are
specialized today. Arm-swinging like a gibbon involves many speciali-
zations of the hands and fingers — elongation of the digits, some spe-
cialized changes in the carpus of the hand, loss of certain muscles or
fusion of muscles, great proportionate elongation of the forearms, and
many other traits that were not present in these early forms. Pliopithe-
cus, a short-armed gibbon from the Miocene of Europe, proves this,
and the same is true of Proconsul, as Leakey has already mentioned.

Just this year we have had for the first time a detailed study of
brachiation among the higher primates, by Virginia Avis. When Keith
introduced the term in the 1890's, he meant arm-swinging among gib-
bons; but this is terribly vague. We now have studies showing how
different apes — and they are different among themselves — compare
with monkeys, how they use their limbs in locomotion. This sort of
combined functional and behavioral study shows that brachiation is
indeed a complex term that covers several different locomotor patterns.
We ought to distinguish these categories from each other.

In my opinion, Proconsul was in many respects a brachiator; that is,
it used its hands overhead when moving along through the trees. Pro-
consul certainly did not move in the same way a monkey does, al-
though undoubtedly it had many monkey-like movements. But this
genus had this freedom of the shoulder, this primary ability to rotate
extensively the forearm at the elbow, and none of the specialized char-
acteristics of the living brachiators. That is very important.

Leakey: May I cut in? The word "brachiation" was introduced by
our chairman. I expressly avoided it. Instead, I referred to "a stage

154 ■ ISSUES IN EVOLUTION

with long arms and short legs," because brachiation has been used in
so many different ways that, unless we define it clearly and agree on
what we mean by this term, it is better avoided. Some of the earliest
fossil apes — Proconsul, and certainly Limnopithecus — had arms ca-
pable of much more rotation and of much freer movement above the
head than many other animals. But this is also true of many monkeys.
That is why we must be careful in our definition of just what consti-
tutes brachiation. As a former student of Keith's, I prefer to use the
word only for the conditions under which primates use overlong arms
for swinging through the trees.

Emiliani: I have seen definitions that would include among brachi-
ators a large proportion of the population of New York City traveling
in the subway.

Hov^ell: This is the whole point, of course. Monkeys are unable
to make many specific movements and patterns of movement that
humans and apes, and especially certain humans and certain apes, can
perform. The apes and modern man — we don't know about fossil
man, but we assume that he's in the same category — perform a variety
of movements, including the equivalent of hanging from straps or
reaching behind the head to pull the left ear with the right arm, which
no monkey can do. This great mobility of the shoulder and the par-
ticular structure of the elbow and wrist are very special and are com-
mon only to man and the apes.

Simpson: This problem of brachiation, then, seems to have been a
pseudo-problem, or at least has been put in the wrong terms in many
discussions in the past.

Bates: It's a shame that we lost our tails. Don't you agree that a
nice prehensile tail would be very useful?

Howell: Whether man ever had a tail is an important problem.
Many lorises do not have tails. Similarly with monkeys: some do and
some do not have tails. The question is particularly relevant for the
origin of much of the supporting mechanism that restrained man's
internal organs during his acquisition of upright posture. So whether
man had a tailed or a tailless ancestor, and how much of a tail it was,
is vital for understanding the acquisition of certain characters of loco-
motion.

Leakey: One of our main difficulties is that we lack data about such
structures as tails from the early part of the period during which the
Hominoidea arose. We always hope that one day we shall find a nearly
complete skeleton of one of these creatures so that we may know
whether they had tails. The recent discovery of the strange primate
Oreopithecus, which is certainly a hominoid, may give us a partial
answer. But even if Oreopithecus had no tail — and I understand

PANEL THREE: MAN AS AN ORGANISM ■ 155

Hurzeler is not yet sure — it would not establish this fact for other
higher primates. For my own part, I doubt that any of the true Homi-
noidea ever had tails.

Simpson: The subject of the tail is like the barking dog in the
night, in that the mystery was that he didn't bark; the mystery in man,
of course, is that we lack tails. There might be something to say about
the dentition of these earliest hominoids.

Leakey: We are beginning to get evidence suggesting that some of
the early primates, such as Proconsul, had peculiarities of dentition
tending toward that seen in the true Hominoidea at a very early stage.
There is even a suggestion that milk dentition of the type that devel-
oped in the Hominoidea may have begun in some of the very early
primates. This needs more study. But I think in the past we have not
adequately understood the character of the canine teeth. We have
tended to overemphasize and to be preoccupied with the size of pongid
canine teeth. I think we must pay more attention to the fundamental
character and morphology of canine teeth in different branches of the
Hominoidea rather than to the size.

Simpson: Of course, the idea that man's ancestors passed through
a stage with large canine teeth has been opposed as a contradiction of
irreversibility of evolution. This is a false application of the principle,
which, as far as it has been authenticated, would by no means exclude
the possibility that man's ancestors had large canines, which were first
enlarged and then reduced. Such sequences have happened over and
over again in evolution. I agree that size is rather trivial compared
with structure and function.

Bates: How do the structure and function of the canines differ in
different forms; that is, how do you tell from looking at a canine how
it was used?

Simpson: I prefer not to answer for humans or hominoids. In some
other groups, you can tell a great deal from the structure of the canines.
There are very gross examples, like the sabertooth tiger, whose canines
certainly functioned differently from those of a rodent that lacks
canines.

Bates: But Leakey was emphasizing that we should study not the
size but the form, and I was wondering What characters in particular?

Leakey: We now have many specimens of the canine teeth of Pro-
consul and of early pongids generally; and I am more and more com-
ing to the conclusion that you can clearly distinguish the teeth of this
genus from those of many other Pongidae. I think we have been over-
emphasizing the size of canine teeth while neglecting their morpho-
logical type.

Howell: These large anterior teeth, specifically the big canines

156 ■ ISSUES IN EVOLUTION

of the gorilla and orang, were considered significant in early theories
of man's origin and relationship to other hominoids. Darwin, for
instance, suggested that the size of human canines was reduced be-
cause of tool use. Actually, the interior dentition is a very complex
structure in all the apes. It is not merely a question of the canines,
either upper or lower; for the canines, both upper and lower, and cer-
tain spatial relationships between them, and the spaces enabling them
to mterlock and to fit with the lower premolar — the first bicuspid
tooth that follows them — are all specialized in a particular way in all
the known apes. This specialization of the canine complex was gen-
erally present in the Miocene hominoids, but it was not nearly always
so extreme as in certain modern forms. This is true even of Proconsul.
The size of the canines is part of a whole pattern that, once it be-
gins, seems to carry along in certain hominoids. Some workers think
this complex, like very long arms, is a characteristic separating the
apelike hominoids from the non-apelike hominoids.

Simpson: This discussion becomes more interesting as we approach
ourselves. The next group, the australopithecines, has made a tremen-
dous stride in the human direction. Leakey, who with his wife just
this summer made one of the major discoveries, is well qualified to
discuss the structure and habits of these animals.

Leakey: The most important point about the subfamily Australo-
pithecinae is that, beyond all doubt, they walked erect: a conclusion
clearly established by the position of their occipital condyles and the
shape of the base of the skull and, in the South African genera Paran-
thropus and Australopithecus, by the structure of the pelvis and limb
bones. These are some of the reasons this subfamily is put into the
Hominidae.

Another reason is their dentition. This group lacks any suggestion
of the type of large canine found in the great apes today; and the
diastema is either absent or very small, quite unlike that of the apes.
Moreover, the whole arcade of the teeth in the upper and lower jaws
distinguishes the Australopithecinae from the Pongidae. In all the
Pongidae, except Proconsul, the molar-premolar series tends to be
parallel or even converge backward, so that the third molars are closer
together than the canine teeth, whereas in most of the Hominidae and
in Proconsul there is convergence from the back toward the front. In
the Hominidae this difference of arrangement is associated with a con-
siderable reduction in the size of the canines, while in Proconsul it is
associated with a great reduction and crowding together of the in-
cisors. Then there is the milk dentition. Putting aside the possibility
in the Proconsul group of a tendency toward hominid milk dentition.

PANEL THREE: MAN AS AN ORGANISM ■ 157

in the Australopithecinae the first lower milk molars are of exactly the
same type as those found in man today, and quite unlike the form
seen in the Pongidae.

Next, let us consider the brains of these creatures. While it is true
that they are not appreciably larger than those of some of the larger
gorillas, they were large in relation to the body size. This incidentally
raises an issue that we shall deal with later, but I should like to say
at this point that mere size of brain is not so important as people like
to believe. Even scientists in other fields repeatedly ask me, "What
was the size of the brain in Zinjanthropus? Was it of human size?"
When taken in relation to total body weight, size has some importance.
But, by itself, size, as distinguished from brain complexity within that
size range, is much less important. There is no reason to believe that,
because the South African Australopithecinae had brains only about
as large as that of a gorilla, their mental abihty was of the same order.
Australopithecus could easily have had a brain of the same size or even
smaller, but much more complex in respect of the cortex and there-
fore capable of much more effective use.

Within the subfamily Australopithecinae of the family Hominidae,
we now have a third member, Zinjanthropus. This form differs in so
many ways from both A ustralopithecus and Paranthropus that it must
be put in a separate genus. In certain characteristics it is much closer
to man than to either of the other two genera. For example, Zinjan-
thropus has a very well-developed mastoid process of pyramidal form;
a much deeper palate, especially in the anterior part; more clearly
defined anterior rim of nasal aperture and well-marked nasal spines;
and an entirely modern type of facial architecture.

These differences indicate a great diversification and branching-out
of different groups of Hominidae at this level of evolution. I wish to
stress this, because there is a growing tendency among anthropolo-
gists, anatomists, and paleoanthropologists to think that man is a
special animal whose evolutionary steps follow more or less a straight
fine without side branches. I dispute this. My concept of the evolu-
tionary development of man is much more complex; and not only can
it not be drawn in Hnear form, but it cannot even be shown accurately
in two dimensions. It is very complex, with many divergent and even
crisscross branches, and emphatically is not a simple sequence of suc-
cessive stages. On the other hand, I do think the australopithecine sub-
family has characters which suggest that the totality of this group
represents an evolutionary stage through which the primates passed
on their way to becoming man.

Simpson: These creatures are beginning to act in ways within your
sphere of interest, Hallowell.

158 • ISSUES IN EVOLUTION

Hallowell: I wonder whether Leakey would comment on three
points: the use of fire by the australopithecines, their capacity for
speech, and their use of tools.

Leakey: There is no evidence of the use of fire by any of the
australopithecines. My colleague and friend Raymond Dart described
his second find of Australopithecus by the specific name prometheus
because he believed that it was associated with carbonized material.
But v/hen it was examined critically by chemists, it was clear that the
black material associated with the bones was manganese and had noth-
ing to do with fire. Remember, however, that the australopithecines
were Hving in Africa, in a warm climate, and perhaps did not need
fire; for they certainly had plenty of opportunity to obtain fire from
natural sources, such as volcanoes.

It is difficult at present to answer the question of speech with any
certainty. I recently examined all the available jaws of Australopithe-
cus and Paranthropus in Pretoria and Johannesburg. In the few speci-
mens in which the inner region of the lower part of the mandibular
symphysis is preserved, I could find no evidence of the type of muscle
scar we associate with the use of the tongue muscles for the rapid
movements needed in speech. Moreover, the whole shape of the palate
in these genera is one I would regard as not being associated with
ability to articulate speech, although certainly capable of uttering
some sounds. I should therefore say that Australopithecus and Paran-
thropus show no evidence of capacity for speech.

We have not yet found a lower jaw of Zinjanthropus, so I cannot
give a positive answer. The depth and general shape of the palate
suggest that when the lower jaw is found, we may find that it was the
type linked with speech, but that is far from certain at present. This
would be another strong indication that Zinjanthropus is truly human.

The third question was whether the Australopithecinae are asso-
ciated with tools. Dart has suggested that a very complex series of dif-
ferent kinds of tools was made by the South African Australopithe-
cinae from the bones and the jaws of animals. My own view is that,
while some of these bones and jaws were used to some extent as natural
tools, I doubt whether they were tools in the strict sense. So far as I
can see, they were not made to a set and regular pattern. I befieve
there is some exaggeration of the evidence used to account for the
accumulation of bones and teeth at the South African sites, but I
cannot discuss that now. I am quite certain that the stone tools claimed
to have been found with Australopithecus prometheus were not tools
at all.

More recently, in an upper level at Sterkfontein, R. J. Mason and
J. T. Robinson found tools clauned to be of the Oldowan culture and

PANEL THREE: MAN AS AN ORGANISM • 159

said to be associated with Australopithecus teeth. A great many more
tools have been found since then, including specimens of the Chellean
type. I am not at all happy about the claim that the associated teeth are
those oi Australopithecus; they could just as well belong to some other
early hominid, such as Telanthropus. I think Robinson would not now
claim what he did in 1956; and therefore I think it is not as yet proved
that the South African Australopithecinae made tools.

In contrast, the genus Zinjanthropus of East Africa was found on a
natural, sealed-in living floor, in direct association with nine very well-
made regular tools of the Oldowan type, together with 176 waste
flakes. Most of the material had been brought in from over four miles
away, and some of it from nineteen miles away. Therefore, it definitely
can be said that Zinjanthropus was a man in the tool-making sense.

Bates: Leakey has a book coming out this spring, a new version
of Adam's Ancestors, which undoubtedly will explain these things.
Raymond Dart has just published a fascinating book. Adventures
with the Missing Link, giving his views on this bone culture; and I
suspect that from these two books one can get a very good idea of
the controversy.

Simpson: Now we have had the commercial. Next, we are going
to discuss the subfamily to which we belong, and I will ask Howell
to summarize some of the fossils that belong to the Homininae.

Howell: By the beginning of the Middle Pleistocene there is good
evidence of man's presence in extensive areas of the Old World —
throughout Africa, in southern and western Europe, and in Southeast
Asia and the Far East. Evidence in western and southwestern Asia
is very poor, largely because of preoccupation with protohistory and
biblical archeology and not enough interest in matters prehistorical
and geological. The great area from the eastern Mediterranean littoral
to and including the Indian subcontinent is hterally unknown, so far
as the important Middle Pleistocene time range is concerned.

In this respect hominines represent a new grade of development
within the hominids; and they seem to have dispersed from a primary
center of evolution. A number of workers think, as Darwin believed
one hundred years ago, that this center was in Africa, although it
might have included areas that are not now geographically part of
the African continent.

Some workers in human paleontology see differences of a specific
level, others of a generic level, between the western, or European, and
the eastern, or Asian, hominines of the Middle Pleistocene. Certainly
there are substantial differences in their morphology. The only way
to express differences in morphology is to give these adequate taxo-

^

160 • ISSUES IN EVOLUTION

nomic rank. Some of these differences seem to be of at least a specific
nature. I shall not develop this point because I think it is not important.

Relatively little is known about the factors responsible for this wide
dispersal of the early hominines; but probably it occurred because the
first hominines — or the first men, if you prefer that term — were both
able and forced by certain pressures to exploit new environments.
They were fully and habitually carnivorous, and meat represented a
substantial part of their regular diet, a further shift from the spo-
radically predaceous and semicarnivorous scrounging of the australo-
pithecines, capable of coping only with small mammals or inmiature
medium-sized mammals and similar animal life. While the earlier
hominines were not yet hunting peoples in the sense of those who lived
30,000 to 50,000 years ago, they were none the less sufficiently com-
petent hunters to deal adequately with a variety of game, including
all the large animals, under relatively diverse ecological circumstances.

The early hominines apparently had an adequate material culture
in stone, with particular types of implements being fashioned ac-
cording to established traditions of manufacture and to consistent
forms. Although its preservation is certainly incomplete, with prac-
tically nothing known of bone or wood implements, for example, this
partly reflects the neglect of this problem by prehistoric archeologists.
A notable exception is Leakey, who in East Africa has excavated
several of the actual living sites of such early peoples. From these
sites, which cover much of the Middle Pleistocene time range, we be-
gin to know how tools were prepared and what kinds of tools were
made, and we can make some inferences about their cultural level.
Other such potentially rewarding sites in various parts of the world
need attention, especially in Europe, western Asia, and India.

So, with the appearance of the hominines, there is evidence of bio-
logical, as well as of cultural, change. Certainly there is evidence of
man's widespread radiation into different parts of the Old World. As
far as is known, these people were not australopithecines in the strict
sense, although often they show resemblances to what probably was
an australopithecine source. Hence most human paleontologists think
that the hominines passed through an early hominid stage or grade of
organization that, broadly speaking, could be called "australopithe-
cine." This may have represented an extremely long period prior to
hominine dispersal.

Simpson: Human evolution occurs against a scale of time that is
slowly being worked out. Emiliani has been doing some exciting work
in developing methods of dating.

Emiliani: I would rather Howell went ahead a bit to introduce the
names of some of the sites.

Howell: I think it is not important to name all the sites. Fifty

PANEL THREE: MAN AS AN ORGANISM • 161

years from now, we hope to have fifty, one hundred, or a hundred
and fifty more. We mention them now only because we have so few.

In western Europe the earhest evidence of man appears near what
we think is the end of the first great continental glaciation, the Mindel.
The site of Mauer, near the town of Heidelberg, is the oldest such well-
dated occurrence in Europe. Fossil remains dating from a somewhat
later time were found at Steinheim, north of Stuttgart, and at Swans-
combe, on the Thames River not far from London. A little younger
than the human remains from Mauer are those from Ternifine in Al-
geria. There are somewhat later sites along the Atlantic coast of Mo-
rocco. In eastern Asia the earliest human skeletal remains are from
Java, from several beds of differing geological age, but all from the
Middle Pleistocene from our present knowledge of the associated
mammahan fauna. In China there is "Peking Man" found at Choukou-
tien, southwest of Peking, one of the few sites providing a satisfactory
population sample. There are australopithecine samples, of course,
and some good samples from later in the Pleistocene, but very little
is known about human populations throughout most of the Middle
Pleistocene.

Emiliani: Ever since it became clear that man was not created
abruptly but evolved slowly by normal processes, a basic task of paleo-
anthropological research has been to attach a time scale to the se-
quence of events in human evolution. Most human and prehuman
fossils have been dated only paleontologically, by determining whether
they are Lower, Middle, or Upper Pleistocene. I shall very rapidly
define the Pleistocene as the length of time since certain maladjusted
species of northern marine moUusks migrated southward to the Medi-
terranean, because it was too cold in the north, and were buried in
the continuous Plio-Pleistocene sequences of Italy. That event was
chosen by the Eighteenth International Geological Congress in 1948
as marking the onset of the Pleistocene. We have only a very rough
idea of when that was.

Since marine mollusks naturally are buried in marine sediments,
it is very difiicult to correlate them with the sediments containing con-
tinental fauna upon which the terms "Lower," "Middle," and "Upper"
Pleistocene are based. Most Pleistocene studies have been based on
continental sediments — on moraines, till sheets, and other glacial fea-
tures or on loess sheets outside glaciated areas. These sediments are
always discontinuous and nowhere represent more than one or two
glaciations, with only one or two interglacial deposits sandwiched be-
tween. For about a hundred years, geologists have been trying to re-
construct the history of the Pleistocene from this very fragmentary
evidence.

The classic scheme of four glaciations separated by three major

162 • ISSUES IN EVOLUTION

interglacials was produced fifty years ago by A. Penck and E. Bruckner
in Austria and southern Germany. Even earlier, North American geol-
ogists had postulated five glaciations instead of four. Actually, both
classifications were valid, since the European fourth glaciation had
two stages that American scholars separated into two different glacia-
tions.

For a complete uninterrupted section covering the whole Pleistocene,
one must turn to deposits formed under water. Lakes with a continu-
ous sequence of sediments are very few, and by far the best possibility
is offered by the deep sea. About 40 per cent of the ocean floor is car-
peted with sediments called "Globigerina ooze," consisting largely of
the shells of pelagic Foraminifera depositing calcium carbonate. After a
brief life these organisms reproduce, and their shells fall to the bot-
tom, where they accumulate at roughly constant rates (2-3 cm. per
thousand years), together with clay particles introduced into the ocean
by rivers or wind.

With modern devices for sampling such deep-sea deposits, columns
as long as 20 meters, covering the whole Pleistocene and going back
well into the Pliocene, have been recovered. From such a column one
can extract at regular intervals the shells of the protozoans that once
lived near the surface and can actually determine the temperature of
the ocean surface at the time these shells were deposited. The method,
devised and developed here at the University of Chicago by Harold
Urey, consists simply in determining the ratio of the two oxygen iso-
topes — O^^ and O^^ — in the shells. This ratio depends essentially on
the temperature. Thus one can reconstruct the variations in tempera-
ture of the ocean surface throughout the Pleistocene. When this was
done, we noticed that in such areas as the equatorial Atlantic or the
Caribbean, where there was some proximity to the ice caps surround-
ing the northern end of the Atlantic, the temperature oscillated about
6° or 7° C. between colder and warmer periods. We have a series of
peaks and valleys representing periods of warm and cold weather —
reflected in cold and warm water — in these areas.

Dating the deep-sea cores is neither so complicated nor so difficult
as dating continental deposits. By radiocarbon methods, which have
a range approaching 70,000 years at present, continental deposits can
be dated back that far. Marine deposits can be dated back to the same
level by this method. Such datings indicate that the last temperature
minimum shown in the deep-sea deposits corresponds to the time of
the maximum advance of the ice in the Northern Hemisphere.

The first attempt to date marine deposits older than 70,000 years
was simply an extrapolation of radiocarbon ages. The method is not
very elegant but is fairly reliable, because sedimentation in the open

PANEL THREE: MAN AS AN ORGANISM • 163

ocean is nearly constant if averaged through a glacial-interglacial
stage. By this method we have been able to date temperature minima
that are correlated with glaciations at 18,000, 65,000, 110,000, 180,-
000, and 275,000 years ago.

Turning to human evolution, we can say that continental fossils
that are correlated with glacial and interglacial stages in the northern
latitudes correspond to the date of a particular maximum or minimum
temperature shown in the deep-sea cores. John Rosholt has recently
verified the extrapolations by direct dating by using two radioactive
isotopes — protoactinium-231 (Pa-^^) and thorium-230 (Th-^^), both
of which are daughters of uranium. Thus our present time scale may
be correct, although, when originally proposed, it was based on rather
flimsy grounds.

This seems to me the best available method of dating human fossils.
Bone itself is physically and chemically very active and is so easily
contaminated that it is practically impossible to date it directly. Mate-
rial associated with bones — shells, for instance — could be dated more
easily, but the attempts that have been made are only preliminary. So
I suggest that the only possibility of establishing an absolute time scale
for human evolution is this indirect method of using the deep-sea cores.

Simpson: How old would you say that Leakey's Zinjanthropus, for
instance, might be, supposing it is about the same age as the Sterkfon-
tein remains?

Emiliani: Australopithecus lived during the so-called Lower Pleis-
tocene, by my estimate perhaps 300,000-600,000 years ago — roughly,
half a milHon years. African sequences are very difficult to correlate
with glacial stages. Pithecanthropus lived during the First Interglacial,
or at least extended through this period, and became extinct about
200,000 years ago. If we consider the Swanscombe skull Homo sapiens,
modern man dates from 120,000 to 125,000 years ago. On the other
hand, the earliest fossils representing modern man may be, instead,
the Fontechevade remains. From what I can gather from published
descriptions, their only non-sapiens feature is a somewhat greater
thickness of the skull bones; and I do not know whether this falls into
the range of thickness found among modern man. Certainly, they look
very modern. The Fontechevade remains date from the Last Inter-
glacial, about 100,000 years ago plus or minus a few thousand years.

Of course, this leaves a great deal of time unaccounted for. The
Hominoidea may have become a separate branch of the primates
as far back as the Ofigocene, roughly 30,000,000 years ago. Then
we see this development through Proconsul and similar Miocene forms,
about 10,000,000 or 15,000,000 years. There follows an enormous
gap, including the whole Pliocene, during which occurred the basic

164 - ISSUES IN EVOLUTION

steps of iliac evolution that made vertical position possible. This fun-
damental step had already been achieved at the time of Australo-
pithecus. Evolution proceeded through various steps from Australo-
pithecus to Zinjanthropus, which I estimate might be 300,000 to 500,-
000 years old. Leakey disagrees. Well, I am willing to make it 600,000 j
years. It is really impossible to determine its age until the African de-
posits are correlated with the deep-sea cores, and that can be done
only through exhaustive studies with pollen and similar techniques.

How^ell: The deep-sea cores are unusually complete and provide
a truly unique succession of events. As Emiliani said, they can be
measured to obtain climatic curves. But I think the curves derived
from the Atlantic and Caribbean cores are not well related to what
is known about the continental Pleistocene stratigraphy. The upper
(recent) end of these cores fits perfectly and confirms everything that
is known about continental sequences; beyond the Last Interglacial —
which lasted from 100,000 years ago or a little more down to 65,000
or 70,000 years ago — the curves seem to be off. The Riss Glacial, for
instance, has three very well-marked peaks in Europe, but the inter-
pretation of the deep-sea cores shows it with only one. This throws
the whole scale off. It means that the dates which are said to be about
300,000 years ago and therefore to measure the First Glacial are, in
fact, probably measuring the very end of the Mindel Glacial. If this
interpretation is correct, these cores are incomplete at the lower, or
early, end of the scale. This in turn means that the Pleistocene lasted
nearly a million or a million and a half years — a length of time that
is much more reasonable and one which most geologists and pale-
ontologists would prefer. Although the method is extremely useful, I
question the present appHcation of the deep-sea curves to the con-
tinental sequences.

Emiliani: F. Brandtner has worked on soil profiles in Austria,
where there are unusually complete soil sequences. His work shows
a perfect correlation — in fact, one that looks almost too good — ^with
the climatic oscillations revealed by the deep-sea cores back to and
including the so-called Great Interglacial, which is, by definition, the
Mindel-Riss.

The Atlantic and Caribbean cores cover only about 300,000 years.
Work on similar cores from the Pacific, which cross the Plio-Pleis-
tocene boundary, has yielded a curve of decreasing temperature from
the Pliocene into the First Glaciation. This resulted in a conjectural
estimate by myself of about 600,000 years for the Pleistocene. At the
present time it is a matter of choice where you put the beginning of
the Pleistocene, but in the future someone will find a way to correlate

PANEL THREE: MAN AS AN ORGANISM ■ 165

the Italian level that was officially estabHshed as the Plio-Pleistocene
boundary with these Pacific cores.

Mostly on Brandtner's evidence, I beUeve that the proposed cor-
relation is probably correct as far back as the Great Interglacial. The
fact that in Europe the Riss Glaciation had three peaks is of no con-
sequence. There were many peaks within the Wisconsin Glaciation
in North America, but the deep-sea cores do not show this because
these peaks were succeeding each other at intervals of about 3,000
years. Every 3,000 years there was a rapid advance of the ice and
then a very rapid retreat, and there were four or five such stages be-
tween 25,000 and 12,000 years ago. None of these is shown in the
deep-sea cores because organisms living on the ocean floor sift the
mud and constantly rework the sediments, so that normal Globigerina
ooze sediments do not show events as close together as 3,000 years.
The oscillations during the Riss Glaciation are comparable to those
of the Wisconsin, which are lost in the deep-sea cores.

Leakey: I agree with Howell that the degree of correlation is good
as far back as 100,000 years, but beyond that it seems much less satis-
factory. Enormous parts of the Pleistocene cores must still be undis-
covered, and perhaps what Emiliani calls the beginning of the Gunz
glaciation is, in fact, only the beginning of the Mindel glaciation. I
do not think that his dates are well established.

Emiliani: They are not established at all yet. First of all, we will
have to substitute absolute data for extrapolations.

Simpson: I think we should discuss the ecology of primitive man,
a subject on which Bates should have some ideas.

Bates: The only real way to establish the ecology of the hominids
and hominines, of course, is to reconstruct their environmental rela-
tions directly, as Leakey is doing. At the moment, however, we shall
have to extrapolate and to use comparative studies of contemporary
primates to infer the conditions of the past.

Population size is an important factor in ecology. Most anthro-
pologists estimate that in a food-gathering culture each individual
needs about two square miles of good territory to survive. Since the
amount of good hunting territory is limited, these early populations
must have been quite small, and the total protohominid or early hom-
inid population of the globe could not have been more than a few
million.

These populations must have been broken up into small groups.
Territorial behavior is universal among contemporary primates. Since
a phenomenon that is universal within a group of related animals can
be pushed far back in time, we can assume that protohominids and

166 ■ ISSUES IN EVOLUTION

early hominids followed a similar pattern. Territoriality would have
several consequences: probably the breeding groups were broken up;
diffusion may have been slowed down; and conflict might tend to oc-
cur between different territorial groups rather than within the group.

Except for the australopithecines and "Peking Man," no fossihzed
aggregations of these early populations have been found. But the evi-
dence from these two exceptions indicates the existence of co-opera-
tive groups of a size larger than the family. This is what one would
expect as a reasonable basis for human evolution.

The essential points of the ecology of primitive man for human evo-
lution are that he was a relatively scarce animal living in social groups
of perhaps forty, fifty, or one hundred individuals — small aggrega-
tions, each with its definite territory, and presumably showing clas-
sical territorial and social relationships.

There is a great deal of discussion of peck-order, the Old Man,
and similar phenomena by psychologists. I think this whole concept
of peck-order often comes from studies of contemporary pongids,
whose behavior may have relatively little significance for human evo-
lution. What I understand from Sherwood Washburn, and similarly
from Ray Carpenter's early work on the howler monkeys and some
recent observations of the gorilla, suggests that peck-order may be
largely an artifact of confinement. It has been studied by S. Zucker-
man in the London Zoo; and among humans it shows itself very well
in the kindergarten and in jails. I cannot see that it is very basic.

Leakey: Primates are generally organized as territorial groups for
food-gathering purposes; this is also true of many other animals. Ter-
ritorial organization, however, is often upset by seasonal climatic
changes, particularly extreme drought, which will bring together for
short periods members of otherwise isolated groups. For instance, a
group of monkeys with a very strong territorial organization will keep
every other monkey of the same species out of their area of a forest.
But when water is in short supply, four or five groups, sometimes in-
cluding different species, mingle at the same watering place for a
time, returning to their own territorial zone, once they have drunk.
I think that the consequences of the brief intermingling of groups that
are otherwise territorially isolated have been overlooked in the past.

Simpson: One topic which must, by all means, be covered is the
evolution of the brain, including instinct and learning as far as these
are pertinent to biological studies of man. Rensch is an authority on
this subject, and I shall ask him to take over.

Rensch: The phylogenetic development of the human brain may
be judged only from a few casts of brain cases. The Australopithecus

PANEL THREE: MAN AS AN ORGANISM ■ 167

cast described by Schepers shows a brain rather similar to that of the
great apes, in that the frontal lobe of the forebrain was not much de-
veloped. The great enlargement of this part of the brain in Neanderthal
Man and in Homo sapiens was very important, since it is composed
mainly of associative regions allowing much more plastic behavior.
As Leakey said, the presence of the motor speech center in the Aus-
tralopithecinae is very improbable, for it is a part of this frontal lobe.
Otherwise, I think, tools would have been developed earher.

I think it is of some theoretical importance that the improvement
of the forebrain took place mainly by quantitative steps. This was one
of the reasons we studied anatomical, histological, and functional dif-
ferences of the brain among related animals of different absolute sizes
at our Institute in MUnster. We compared rats and mice, giant and
dwarf squirrels or bats, large and small races of domestic fowl, large
and small lizards and fishes.

We could tentatively establish several rules. Particularly in larger
mammals, the isocortex (the most complicated and progressive five-
and seven-layered part of the cortex) grows faster (with positive al-
lometry) than the whole brain during the main postnatal growth pe-
riod. This allometry does not always stay the same during phylogeny;
the allometrical exponent is often altered. Normally, however, the
general tendency remains unchanged. Hence adults of larger species
have a relatively larger isocortex than smaller related species and con-
sequently have better mental capabilities. They can learn more tasks,
and more difficult tasks, and can retain for a longer time. I believe
that the same phenomenon occurred when man originated; the iso-
cortex was enlarged because of its positively allometrical growth. Such
quantitative steps of improvement were possible in all levels of brain
increase, since spontaneous plus mutations are common and would
be selected for because more plastic behavior is advantageous.

By such quantitative steps, however, new qualitative characters
could also arise. Broca's region — the motor speech center — is a typical
example. If this region developed by purely quantitative increase in
the cortex, excitations would flow in from all the neighboring regions
— that of tone memory, those for movements of tongue and lips, and
those from the associative regions of the frontal and temporal lobe.
Hence this new region was preadapted to become a motor speech cen-
ter. The development of language allowed the formulation of more
abstract concepts, labeled by words. It made the exchange of personal
experience and the development of traditions possible. And this was
the main basis for the development of human culture.

I believe, then, that the shift from the more animal-like behavior
of the australopithecines to more human behavior in Pithecanthropus

I

168 • ISSUES IN EVOLUTION

and Homo was primarily effected by quantitative steps. Would you
agree, Leakey?

Leakey: I think that we have not yet fully mastered the study of
brain casts and that available casts of the earlier primates are still
far too few to make such a study well founded. I should say that brain
casts of the South African australopithecines show distinct differences
from comparable casts of higher apes; but much more data are needed.
Later I hope to send Rensch a brain cast of Zinjanthropus to study.

Simpson: Hallowell, have you anything to say about the evolution
of the brain?

Hallowell: Only a short time ago this problem was less well
defined than it is now that evidence of brain expansion within the
evolution of the hominids is clearly established. Assuming an absolute
increase in the number of neurons available or in the space between
them, this increase in size brings up the problem of its relation to the
sociopsychological aspects of behavioral evolution and the cultural
adaptation characteristic of Homo sapiens. Even if we do not have
final solutions yet, the questions that Rensch and Leakey raised are
among the most important before us.

Howell: I doubt that the expansion of brain size actually was
gradual; probably this effect is an artifact of the record. In any case,
there was an increase in size up to 65,000 or 70,000 years ago, and
after that the essential structure of the brain seems to be maintained,
although it may be arranged in a slightly different form.

During the Middle Pleistocene there was a gradual increase in the
size of the brain and certain changes in form. These changes included
great expansion of certain association areas of the parietal and upper
temporal regions and, as far as we know, were associated with the
expansion of memory, learning from experience, and the storing-up
of information. These were also related to the reception and transmis-
sion of speech. Within the coming years there will be major advances
in this field, providing answers to problems that can only be posed
today.

Leakey: The evidence available indicates that, even in persons of
comparable body weight, absolute brain size is not a controlling factor
in ability, which is connected with the quality of the brain. I think
my friend Rensch really agrees with this. Some British studies in which
I had a part showed that the brain size of leading scientists was often
much less than that of pugilists. Looking at those sitting around this
table, I can see a tremendous variety of absolute brain sizes; and I
stress that quality, rather than brain size, is important.

Bates: It may take more intelligence to be a pugilist.

Leakey: That is possible.

PANEL THREE: MAN AS AN ORGANISM ■ 169

Rensch: Of course, the phylogeny of the human forebrain involved
quahtative changes, but these could have originated by quantitative
steps. All the special cells of the human cortex — the pyramidal, gran-
ular, bifurcated, star-shaped, and compass cells — are also found in
the cortex of monkeys. In the brain of Homo only, have certain re-
gions and areas been added, and these are characterized only by spe-
cial increase in the number and density of neurons and cell layers —
a difference that can originate by quantitative steps.

Leakey: We shall have to agree to differ.

Simpson: I am going to expedite our discussion by mentioning that
from his most remote ancestry man has been subject to the same genetic
factors of evolution as those discussed yesterday. Undoubtedly, man
is still subject to these and is still changing in response to them, al-
though, of course, the situation has become complicated by other fac-
tors.

Next I shall ask Bates if he wants to add to what he has already
said about ecology.

Bates: I would like to interject Harry Harlow's idea that in look-
ing at man we confuse capability with accomplishment and that a
rather sUght anatomical shift in the brain, in instincts, and so on can
lead to the beginning of culture, which then makes an enormous dif-
ference. As an animal, man is not particularly unique, but as a cul-
ture-bearer he is tremendously different.

Considering man as an ecological agent over his evolutionary his-
tory, it seems to me that a very curious thing has happened. Through-
out this whole period and now at an accelerating rate, man has been
removing himself from particular biological communities so that he
no longer belongs to a biological community in any sense. The tend-
ency of civilized man and food-producing man has been to eliminate
competitors and to narrow down food chains. These effects make man
a very interesting animal from an ecological point of view.

Simpson: It has often been said that man is pedomorphic. The idea
of pedomorphism is that juvenile characters of an animal are some-
times carried over into the adult state and, as time goes on, more and
more juvenile characters come to characterize the adult. It has been
suggested that human adults somewhat more closely resemble a juve-
nile ape than an adult ape; and therefore the suggestion that man is
a sort of pedomorphic ape, or at least a pedomorphic primate, has
become quite popular. One very often finds it in textbooks. Perhaps
Waddington can give us his ideas on this subject.

Waddington:"i can speak only from the point of view of general

170 • ISSUES IN EVOLUTION

biology rather than from that of human embryology. The concept of
pedomorphosis seems to come from the early days of evolutionary
theory, when biologists tried to explain development by saying it was
influenced by phylogeny or reflected the phylogeny of the group. Bi-
ologists today think of embryonic development as being produced by
the interaction of the genes in the fertilized egg with the environment.
We consider new steps in evolution the result of modifications of
ontogenetic development, but in general we would not suggest any
direct causal relationship between the phylogeny of the group and
the individual ontogenetic development. In my opinion, the whole
sphere of discourse to which the word "pedomorphosis" belongs is
rather old-fashioned. I would not be at all surprised to find that some
features of the present human adult may be compared with juvenile
features of our ancestral forms and that in other features the relation
may be the other way around. But in evolution one has to deal with
all sorts of modifications of developmental sequences item by item
rather than with general alterations of the entire sequence as a whole.

Simpson: That seems very sensible. Howell, do you have anything
to add?

Howell: I agree completely. As Waddington suggested, this prob-
lem can be approached in a much more fruitful way; and I think his
own studies on subhuman organisms have shown this.

A more detailed understanding of different patterns of growth is
needed. Physical anthropologists are just at the point where, with
sufficient studies on living hominoids and with a better fossil record,
they can put into clearer perspective differences that, at one time or
another, have been attributed to pedomorphism, neotony, and other
catch-all phrases that are loosely used to cover phenomena about whose
mechanisms we are essentially ignorant.

Simpson: Perhaps we should move on into the area of overlap
with Panels Four and Five and thus, in closing this panel, form a
bridge to these. I should hke to make the point that we are looking
at cultural evolution from the biological standpoint and that cultural
evolution, after all, is also a biological adaptation.

Hallowell: Several points touched on in this panel indicate a
need to phrase some of these problems in terms of a preadaptive stage.
This approach fits in with Simpson's idea that, since man is not only
an animal but a primate, the cultural adaptation studied in anthro-
pology must, in the last analysis, be interpreted as an evolutionary
process.

Bates mentioned ecological adjustment. I think that in this con-

PANEL THREE: MAN AS AN ORGANISM • 171

nection we need more information about social organization among
the living primates. If we break down the terms "social" and "social
organization," we can study primate groups in terms of role differ-
entiation, which H. S. Jennings years ago pointed to as the basis of
any kind of social organization. If some such concept as "role organ-
ization" is used, then I think the dominance gradient becomes one
aspect of role differentiation; and, as you know, there are experts in
role theory among sociologists. We might consider the social structure
of non-human primates a preadaptive stage.

Incidentally, I understand that systematic studies at the Japan Mon-
key Center have shown this dominance gradient to be directly related
to the socialization of new eating habits. Here again, a phase of adap-
tive social life among non-human primates involves social transmis-
sion of habits.

It seems to me that cultural adaptation could not have developed
in hominid evolution outside the context of a system of social action.
The complete antithesis would be to assume that any kind of cultural
adaptivity could have developed among soUtary animals. Thus some
kind of organized social existence must be a preadaptive stage to cul-
tural adaptivity. This development, in turn, could not have taken
place without certain organic developments, particularly the expan-
sion of the brain, which in the end made cultural adaptation possible
through symbolic mediation.

Bates: The co-ordination of hand and eye involved in chipping a
flint enables you to learn how to fly an airplane.

Simpson: Waddington, I don't think we should close without ask-
ing you to elaborate on some of your ideas, particularly your sugges-
tion that, in culture, receiving is as important as transmission.

Waddington: One of the problems to consider in the evolution
of man is the relation between the specifically human evolutionary sys-
tem and the general biological evolutionary system. The latter is de-
pendent on genetic transmission through the chromosomes, the former
on transmission by social mechanisms. Both systems succeed in bring-
ing about evolution, and both function at the present day. However,
if you compare the rate of advance which they have produced — for
instance, if you compare the speed with which man, with his specific
evolutionary mechanism, evolved the ability to fly by means of ma-
chines, not forgetting the number of miles per hour he can go, with
the rate at which reptiles learned to fly — you can easily see that the
human evolutionary mechanism is astonishingly rapid. Perhaps man
could speed up his biological evolution by a small factor, but it would

172 • ISSUES IN EVOLUTION

be exceedingly difficult and probably quite impossible to make it into
a process comparable in efficiency with the sociogenetic mechanism
of evolution.

In fact, the biological process seems at present to face man more
with evolutionary dangers than with evolutionary possibilities. It carries
the danger of rapid evolutionary disintegration if the process of nat-
ural selection in human populations gets out of hand; and in com-
pensation for this it offers the possibility only of very slow evolutionary
progress. The social processes of evolution, of course, also carry dan-
gers of regression as well as of advance; but the dangers are perhaps
easier to see in advance and to mitigate, while the possibilities of ad-
vance might be very much more rapid than those offered by the bio-
logical process. Although dangers and potential advances are offered
by both processes, it seems to me that at present our positive task is
to concentrate on the development of our sociogenetic evolution, while
not neglecting the negative task of guarding ourselves against the pos-
sible harmful effects which could arise from the biological mechanism.

My second point concerns the actual mechanism by which informa-
tion is passed from one generation to the next in the sociogenetic sys-
tem. I feel that in the past not enough attention has been paid to con-
sidering, not how this information is transmitted, but how it comes
to be received. It is no use telling somebody something unless he is
willing to believe it. The whole system of human culture is based fun-
damentally on a mechanism of communication and transmission that
requires people to be brought up in such a way that they develop a
mental setup which leads them to be ready to believe others. They
may not like what they are told; and at some stage they may test it,
find it is all nonsense, and reject it; but that is a secondary process.
Perhaps the testing of transmitted information corresponds to natural
selection, but, before it can operate, there must be something that cor-
responds to heredity. Ideas or statements must be reliably transmitted
before they can be tested.

Now the requirements for a mechanism that will transmit some-
thing so that it is received at the other end need much more thought
than they have had. I have never really seen this properly discussed,
and what follows are my own personal and tentative ideas. As far as
I can see, the molding of the newborn human individual into a being
ready to believe what it is told seems to involve many very peculiar
processes, which can be explained only in terms of such notions as
the formation of the superego and the repression of the id. Whether
notions of this kind are true in detail or not, the molding of the baby
into a transmission-receiver seems a difficult and complicated and
even slapdash process, and not at all what one might have thought

PANEL THREE: MAN AS AN ORGANISM ■ 173

out if one had set out to design this job. A frequent result of the process
seems to be that people believe much too much and believe it much
too strongly. The process that evolution has provided us for doing
the job seems often to lead to considerable exaggeration of the ability
to believe.

However that may be, it seems clear that any social transmission
of information must depend on the formation of people ready to re-
ceive it. That means that their minds must be so built that they accept
information coming to them from outside. In man this readiness to
accept is produced by a mechanism that involves the formation within
the mind of mental systems that carry authority and can therefore be
beUeved. Now the mental system that carries the greatest authority
and can be believed most thoroughly is the set of beliefs and notions
we categorize as "ethical." The good is that which we regard as hav-
ing the greatest authority in determining the way in which we should
spend our lives.

The point I wish to make is that the appearance within man of
ethical belief is a result of the processes that mold him into a being
capable of acting as a receiver of socially transmitted information. I
dare say it might be possible to conceive of molding man into an in-
formation receiver in some way other than the particular method by
which the process actually occurs in the human race at present. If the
psychoanalysts are to be believed, the process we now use is more
eccentric than one would have thought possible. But I think that some
sort of system by which the mind comes to be willing to believe what
it is told is necessary. That means that there would have to be formed
within the mind some sort of authority-bearing system. Therefore, any
being capable of sociogenetic evolution of the kind that man has de-
veloped would also have to entertain ethical or quasi-ethical beliefs.

So I think that there is an absolutely essential connection between
human evolution, based on the specifically human sociogenetic mech-
anism, and the existence of such things as beliefs about ethics and
values. That man is an ethical being is an absolutely essential part of
the workings of his characteristic evolutionary machinery.

Simpson: Rensch, would you be willmg to suggest what you think
man's biological future might be?

Rensch: Well, it is a bad job to be a prophet. I believe that in
many respects our somatic development has come to a standstill, al-
though selection is still operating to some extent. Particularly, I doubt
that the brain will expand further, since there will be no selection
pressure in this direction. The main alterations will perhaps be caused
by a great increase in recombination of genes.

On the other hand, man's future seems unpredictable, since we are

174 ■ ISSUES IN EVOLUTION

the only living beings capable of directing our own future evolution.
And it will be absolutely necessary that we should try to do this. As
Waddington suggested, the steady mutations that produce mainly bad
characters will cause a regressive development. I believe that it is the
duty of biologists to discuss the problems of the human future, even
if this is not exact science but only speculation.

I would like to raise a final point. We had no opportunity to dis-
cuss human instincts, which are of great importance. I believe it to
be the typical human fate that our inborn drives always conflict with
the actions of so-called "free will." One sees this most clearly in our
reproductive drives, which are similar to those of other mammals.
The double motivation of human actions by such drives and by in-
sight sometimes leads to conflict, in this case to adultery for instance,
or illegitimacy, or to steaUng children because of the mighty maternal
instinct. Of course, human beings normally act according to certain
customs, morals, and ethics; but the instincts I mentioned are also
an important component of our motivations. Hence, to avoid future
conflicts, we must try to channel these drives into harmless directions,
as we already divert our instincts for fighting and for rank to football
and the like.

Looking forward to the human future, I would like to repeat that
it is a bad job to be a prophet. The matter is so compUcated that I
would say that the future is unpredictable.

Simpson: I shall ask Hallowell whether he would add anything
about the possible cultural future of man.

Hallov/ell: I would rather comment on Waddington's remarks. I
think that it is important to recognize as differentia of this cultural
adjustment of man not only that we do have social systems with cul-
tural transmission but that these are systems of social action, where
you have a normative orientation in all aspects of life. Human societies
function in terms of acquired values, which are part of the socializa-
tion process of the individual, and this becomes part of the particular
kind of adaptation we have made. So, for the system to function, so-
cial sanctions are necessary and information or knowledge must be
transmitted in terms of beliefs held by the individual.

Simpson: I think that that is a very good final word. I am not go-
ing to try to summarize. We are covering such a tremendous topic
that the whole session has to be a sunmiary; so I shall simply declare
the meeting adjourned.

PANEL FOUR
THE EVOLUTION OF MIND

Chairmen: Ralph W. Gerard and Ilza Veith

Panelists: Henry W. Brosin; Macdonald Critchley; W. Horsley
Gantt; A. Irving Hallowell; Ernest Hilgard; Sir Julian
Huxley; Alexander von Muralt; N. Tinbergen

Topics for Discussion

1 . Behavioral science. — Darwin's work has had a tremendous impact
on the behavioral sciences. These, in turn, have contributed anal-
ysis and experiment pointing up problems in the evolution of brain
and mind. Past benefits, present gaps, and future applications are
seen in these areas, to be exempHfied by the panelists in the several
disciplines.

2. Orientation and methodology. — The evolution of mind and be-
havior can (must?) be studied in the same manner as that of any
other organic function. New, but compatible, problems and criteria
and methods are involved.

3. Mind. — The relation of subjective to objective description is espe-
cially important in comparing humans and subhumans as to mind
and behavior. Many aspects of mental function appear in the ani-
mal world, such as organizing stimuli into perceptions, developing
emotional attitudes, performing "purposeful" acts, using and even
making tools, learning by imitation, achieving abstractions, per-
haps operating with values. It is not a necessary consequence, how-
ever, that animals possessing such attributes have consciousness
( awareness, self-awareness? ) .

4. Culture. — Other manifestations of mind are harder to trace below
man, from culture back to protoculture. A useful formulation of
successive stages is the following: learning, signaling, communica-
tion between individuals, transmission of learning through a group
and on to another generation, use of symboHc communications,
self-awareness, and group standards and morals. At the civilized

175

176 • ISSUES IN EVOLUTION

level these are developed as language and ideas, applied to man's
understanding of his world and himself in science, art, and phi-
losophy.

5. The biological basis. — The brain has evolved in complexity of
structure and function, as behavior has evolved in individual rich-
ness and group interrelatedness (culture). The improvements in
the neural machine and its performance are related; indeed, cul-
ture, involving such performances as tool using, has probably urged
on the biological enhancement of the nervous system.

6. The sociological basis. — With the advent of civilization, genetic
evolution has been largely supplemented by cultural evolution; the
new idea does not await the mutated gene. Man is now in a posi-
tion to supplement his information processing as he did earlier his
muscles and senses, and he can control even his genetic future and
perhaps guide the biological evolution of his brain. Here valid
scientific knowledge merges into value judgments, and the danger
of maladaptive developments is great.

The Discussion

Gerard: Our general assignment is to trace the evolution of mind,
behavior, and brain — an area that has been rather neglected in the
ordinary disciplines of evolution, probably because behavior leaves
few fossils. Under items 1 and 2 of the agenda, we shall examine the
assumption that mind can be studied in the ordinary mode of biological
science, although involving rather different problems. We shall then
move on to examine the changes through evolutionary history in the
behavioral capacities of organisms — the increasing richness, speed,
sensitivity, and variability of behavior — and see what inferences can
be made as to what is happening to mind along with these behavioral
changes. In item 3 we shall look particularly at those aspects of mental
function that seem clearly present below man; in item 4, at those about
which there would be considerably more doubt. This is the same prob-
lem of continuity versus discontinuity, or the size of the gap that de-
velops, which the previous panels faced. In items 5 and 6, we turn
to the mechanisms or the basis of this evolution in behavior: in 5,
paying particular attention to the development of the bodily organiza-
tion of the biological machine, and in 6, paying attention to the epior-
ganismic or social level and the influence of culture, transmitted sym-
bols, and the like. So much for our general orientation and planning.

Every organism — indeed, every species or every system of any kind
— is engaged throughout its life in riding two rails: the "desired" —
the equiUbrium state or direction or goal toward which it is moving

PANEL FOUR: THE EVOLUTION OF MIND ■ 177

— and the actual, or real. The environment is continually disturbing
the flow in time, perturbing the system; and it is obvious that the
smaller the change an organism can detect, the more sensitive its per-
ception of an impending disturbance and the more rapid the adjusting
responses it can marshal — in other words, the better it can handle
information — the more effectively will it do this "tracking" job and
keep on the line it wants to travel.

Earlier panels brought out that in metabolic processes and basic
reproductive processes there has been very little evolutionary change
from microbe to man. But behavior has evolved explosively; and in
man there are great riches of capacities and mechanisms. This is really
the basis on which organisms are ordered as higher or lower by bi-
ologists.

The reaction to the environment was initially and primarily to the
physical environment; in later evolution, more importantly to the
biotic environment; and in still later stages of evolution, and not only
in man, to the social environment.

All systems — from molecule through cell, organ, individual, small
group, to larger groups of species or communities — have three major
attributes: a certain "being," or architecture; a certain "behaving,"
or function; and a certain "becoming," or history, that involves evo-
lution, development, and learning at different stages. Our problem is
particularly involuted because we are really concerned with the "be-
coming" of behavior. This means that at each stage we must be con-
cerned with whether we are dealing with a racial, evolved attribute
common to all members of the species; with something that is fairly
common because of the uniformity of embryonic or like development;
or with something quite distinctive and depending on the individual
unique experience of the single organism. Thus species evolution, com-
mon development, and individual learning play together on the final
behavior. It is exciting that mounting evidence relates these to the
nucleotides. The fixation of experience at the racial level, which we
learned in earlier sessions depends on changes in the RNA molecule
in reproductive cells, is paralleled in the fixation of individual experi-
ence — that is, learning — by comparable changes in RNA molecules
in the neurones of the brain.

[The above considerations indicate that the panel faces a number
of questions, and it is understandable that the disciplines represented
here are far-flung, ranging from ethology to the history of medicine.] *

[There is, first, the basic question of subjective and objective, and
the validity of interpreting between these on the basis of observable

* These bracketed paragraphs were omitted during the panel for lack of time and
were submitted in writing after the session.

178 • ISSUES IN EVOLUTION

evidence. Closely related is the use of causal notions, particularly of
statements crossing between the languages of mind and body. An
idea cannot fire a neuron, nor, in a rigorous sense, can ether produce
unconsciousness. Part of the same problem is the use of such in-
tervening variables as "consciousness," "attention," or "will." A
third issue concerns quantitative measurement versus qualitative de-
scription or pattern specification; and the closely related problem of
the precipitate rise of complexity (and of information) as we move
to the higher-level systems of the Uving and the social.]

[Although we shall not explicitly discuss the remaining three topics,
I list them for completeness. First: What is the role of individual ex-
perience in "becoming"? The newborn eye and brain must see pat-
terns in order to develop the capacity for pattern vision; and even
in very early development the actual anatomical patterns of nerve
paths are determined by their functional connection with other parts
of the nervous system or the periphery. Natural selection can operate,
if not on experience as such, certainly on the ability to profit by ex-
perience.]

[Next, what environmental changes constitute stimuli? Evolution has
not increased the sensitivity of receptors to all environmental stimuli
or stresses. Only certain radiations, movements, substances, etc. have
carried meaning to organisms — indicating food or danger or giving
guidance or the like — and so have helped direct evolution. Worry
requires a worrier; stresses are such only if the organism is coded to
them and they carry meaning. This is comparable to the encultura-
tion of the young in a society; perhaps even the poet is a kind of sensi-
tive social reactor.]

[Finally, there is the relation between the role of an organism as
a total individual and as unit or member of some superordinate group
— a society or ecogroup — and its behavior. There is a continuing con-
flict between the inborn rigid responses, the simple motor and the
more complex emotional reflexes, and the more flexible learned be-
haviors, involving reason and adaptation. The former depend over-
whelmingly on inborn neural mechanisms, those of the brain stem
and the limbic system of the cerebrum, which have changed little over
mammalian or vertebrate evolution; the latter depend primarily on
the cerebrum and mainly the neocortex, which have changed vastly
in mammals and particularly in primates. Man's limbic system is ap-
proximately the same in size and organization as that of a cat or rabbit;
his neocortex is incomparably larger and more complex.]

With this general introduction, then, I am going to ask the mem-
bers of the panel to give their own views on this problem of the ap-
proach to the mind; and I hope they will also indicate the kinds of
methodology that their disciplines offer.

PANEL FOUR: THE EVOLUTION OF MIND ■ 179

Brosin: I am a physician, psychiatrist, and psychoanalyst, inter-
ested in Darwinian evolution because of its profound influence on
biology and the other behavioral sciences and therefore on my field
of psychiatry, which is, of course, related to and dependent on all
these fields of human behavior.

One might define or regard mental disorders as biological deviants
or failures in the working of an organism. They may range from such
purely genetic failures as the single specific-gene enzyme deficiency
in the phenyl-pyruvic acid-oligophrenias, or in focal epilepsy, to the
much more complex stress disorders or the familiar character dis-
orders. Consequently, our methods of study must vary with the data
we examine. The methods appropriate to astronomy and geology may
not be entirely satisfactory for human behavior, particularly if we
include the so-called irrational components. In general, we try to
use all useful empiric or pragmatic techniques, from quantitative meth-
ods in neurophysiology or biochemistry to methods that we believe
are similar in all respects to the natural history methods used by Dar-
win and employed in medicine and biology centuries before quantifica-
tion became possible.

We have much reason to believe, with Darwin, that systematic
study of human behavior, including verbal productions, dreams, delu-
sions, hallucinations, and phobias, is both possible and productive.
Verbal behavior is a vital part of the total stream of communication,
including the non-lexical vocal modifiers and the kinesic or body-
motion markers defined in the past by Edward Sapir and Leonard
Bloomfield, of the University of Chicago, which can now be recorded
by film and tape. We expect much more accurate delineation of these
systems and thereby should gain new data and new hypotheses. At
the human interaction level, our units of study are patterns, shapes,
relations, and arrangements rather than space or time units. We are
now looking forward to much more inciteful and comprehensive pe-
riods when we shall have better concepts and methods for dealing with
these complex units.

Critchley: I am a practicing medical doctor, not a biologist or
a psychiatrist. I am an organic neurologist, and as such my interest
has been the breakdown of speech in man — that is, speech disorders
caused by brain injury and brain disease.

Now, in order for speech pathology to be adequate, it should be
tied up with a knowledge of, or study of, speech in the normal human
subject. I suppose that this is the background or context of this par-
ticular panel discussion and the reason we are here.

As one primarily interested in language, I would plead for the most
rigid employment always of a terminology that is simple, clear, and
precise. The growth of ideas and of knowledge has so outstripped

180 • ISSUES IN EVOLUTION

the growth of our vocabulary that there is always a very real danger
of lapsing into confusion. The language used by scientists runs the
risk of being not fully comprehended, not only by the world at large,
but even by other scientists within the same discipline and, of course,
in other disciplines also.

The two devices already used to circumvent this difficulty are in
themselves potential sources of error. One very obvious device is for
science to erect a vocabulary as it goes along by coining new forms,
rigidly defining them, and then always using them in their precise
connotations. The alternative is either to borrow words from lan-
guage in common use or else to filch terms from the vocabulary of
other sciences and then to endow these with our own private mean-
ing — a meaning sometimes quite different from the original and one
that may differ widely from individual to individual. This is a most
fertile source of confusion. Biology, I suppose, is not a conspicuous
offender, but I am sure that psychiatry, psychology, and philosophy
are often seriously at fault here. Most of our ordinary talk is, of course,
fundamentally built upon metaphor; but when you find metaphor
piled upon metaphor upon metaphor again and simile added to anal-
ogy, there is a very great tendency to lapse first into clichedom, then
into jargon, and finally into gobbledegook. Like Voltaire, I would
suggest that each of us should be prepared, if called upon, to define
his terms at a moment's notice.

Gerard: But please exercise that right with caution, or we shall
never get beyond item 1.

Gantt: I am from the Pavlovian Laboratory at the Johns Hopkins
University, and the psychophysiological laboratory in the Veterans
Administration. I study both normal and abnormal aspects of be-
havior, including the causes of psychiatric diseases.

At the present time I am especially interested in high blood pres-
sure and the psychogenic or nervous causes of cardiovascular disease.
The methods I generally use are those of the conditional reflex. In
support of Critchley, I may say that this method gives us precision and
a kind of data less dependent on language.

I learned the conditional reflex method from Pavlov. Just after I
finished interning, I went to Russia with the American Relief Ad-
ministration under Herbert Hoover, when we were feeding ten million
Russians during the famine. I had the honor of meeting Pavlov there
six years after he had officially died, according to the Encyclopaedia
Britannica, which formerly placed his death at 1916. I began working
with Pavlov to learn his methods and continued for six years. This is
my earliest remembrance of the feedback mechanism; so I feel that
Pavlov gave me more than I was providing.

PANEL FOUR: THE EVOLUTION OF MIND • 181

Hallowell: I suppose I might call myself a human animal of a
different variety but perhaps of the same species as the gentlemen who
have just spoken. I would define myself as a cultural anthropologist
with psychological interests. In the past, these interests led me to study
the relations of culture and personality and in recent years have led
to my interest in problems involving the psychological dimension of
human evolution.

For a long time, anthropologists have used the possession of a cul-
tural heritage as a criterion for differentiating man from other animals.
Problems of cultural and social evolution were widely discussed in
the nineteenth century, and we shall hear contemporary discussion of
this topic tomorrow at the fifth panel. I think, however, that there is a
gap in our knowledge of the roots of a cultural mode of adjustment in
man. That is why I used the title "Self, Society, and Culture in Phylo-
genetic Perspective" for my contribution to this conference. There is
a psychological dimension here. It is difficult to investigate, and I fear
that my methods may be relatively imprecise compared with those of
the other panelists.

Veith: My field, the history of medicine, might be thought of as
the hidden link among all the specialties that deal with evolution, for
medical historians deal with evolution in many different ways. With
the emphasis on medicine, we are concerned with the influence of evo-
lutionary principles on medical thought, including, of course — and
in my case especially — that of psychiatric thought; and we deal with
such examples as the direct influence of Darwinism on the work of
John HughUngs Jackson, Sigmund Freud, and others. Again with the
emphasis on medicine, we study the evolution of physical and mental
diseases throughout history; and we try to account for the disappear-
ance of such diseases as the mental and physical epidemics of the
Middle Ages. We also try to account for the ascendancy of apparently
new and often equally menacing forms of disease. As medical his-
torians with the emphasis on cultural and social history, we try to re-
late scientific facts to their cultural environment. Thus we deal with
man's concept of creation and evolution before Darwin and with the
impact of Darwin's work on the cultural world that followed him.

My own interests have especially concerned non- Western — that is,
Far Eastern — evolutionary reasoning and its relations to the cultural
and even political development of the Orient. It has been a most en-
lightening observation that in China the human mind was able to con-
ceive of creation in evolutionary terms at least three thousand years
ago and that some of the greatest philosophers emphatically endowed
the lower orders of life with mental faculties that approached the
human level.

182 • ISSUES IN EVOLUTION

Hilgard: I am an experimental psychologist. What this means is
simply a psychologist who tries to work on problems that can be stud-
ied in the laboratory. It is our faith that this does not limit us very
much, but this faith has to be justified by what we do. My own work
has been chiefly in learning and motivation; and if Critchley will per-
mit me to use some terms from the vernacular, I have more recently
been working on states of consciousness altered from the normal —
such as dreams, hallucinations, and hypnosis.

The justification for a psychologist's being on a panel about evolu-
tion is clear enough from psychology's position between the science
of biology, on the one hand, and the social sciences, on the other. On
the biological side is comparative psychology. Physiological psychol-
ogy is simply one with the biological sciences, and here the debt to
Darwin is clear. On the social and personaHty side, that debt can also
be traced, largely through Darwin's cousin. Sir Francis Galton, who
began the studies of human inheritance and invented the contrast be-
tween nature and nurture that we use so much in talking about human
intelligence.

Huxley: My approach to the evolution of mind has been comple-
mentary to Hilgard's. I have always tried to look at this problem from
the point of view of a naturalist — the same sort of attitude that Charles
Darwin held. I first became interested in this general subject while
studying the courtship of birds, in asking myself what role mind played
there. And as a young man I was very much preoccupied with the
development of my own mind and behavior and also with that of my
fellow men and women. My main concern throughout my biological
career has always been evolution, and I have tried to link the various
evolutionary fields into a unified picture through comparative study.

What has impressed me most — and I hope this will come out during
these discussions — is that during the course of evolution on this planet
quality has somehow arisen out of quantity, and the subjective has
arisen out of the objective. And, of course, that happens in the de-
velopment of every one of us, too. Another trend that occurs both in
individual development and in evolution is that the patterns of organi-
zation of mind and its associated behavior move to higher levels.
Finally, one finds the emergence of this or that new quality or char-
acter of mind, which in turn affects later evolution; and mind seems to
have played an increasingly important role as evolution went on.

VON Muralt: I am a man who likes to stick electrodes into nervous
material and study the effects: that is, a neurophysiologist. When the
morphologist studies life, he finds an enormous variety of form and
function, while the physiologist, on the other hand, is surprised by the

PANEL FOUR: THE EVOLUTION OF MIND ■ 183

great uniformity of the basic mechanisms. I should Uke to give an ex-
ample. We are studying such distantly related animals as the North
Atlantic squid, the electric eel, the torpedo, the spider crab, the frog,
the cat, and the monkey. We find that the only form of sending a
message through the nervous system is the nervous impulse, which is
exactly the same in the squid as in the monkey. We fimd only two
modes of conduction of this impulse: in the lower animals, continuous
conduction; in the higher animals, conduction in jumps, which we
call "saltatory conduction." Studying the chemical substances used
for transmission throughout the animal kingdom, we find, generally
speaking, only two: actylcholine and neuroadrenalin. And as far as
we know today, the only substance used in nervous systems for the
supply of energy is adenosine triphosphate, ATP, with its energy-rich
phosphate bond.

How did this uniformity evolve? There are several possibilities.
Possibly these basic living mechanisms are protected in the genetic
background, so that no mutations and no changes can occur. That is,
they are set apart from evolution. Another rather interesting possibility
is that this uniformity of biochemical and biophysical mechanisms may
be the result of evolution; and here we are starting to think of evolu-
tion as two-dimensional. We have morphological evolution from the
primitive form up to the higher, more complex forms; and in the op-
posite direction we have evolution from a rather complicated biochemi-
ical and physical background to a very simple pattern, which is now
uniform for the whole animal kingdom.

L. J. Henderson's book. The Fitness of the Environment, showed
that the physical factors on this earth are apparently such that life
was possible because of very specific and unique qualities of water,
carbon dioxide, the tetravalent carbon atom, and the like. Perhaps
this limited number of chemical possibilities is a principle for selection
that has created this uniformity throughout the basic mechanisms.
This is one of the problems with which the group of neurophysiologists
jl represent here is concerned.

Tinbergen: I am a zoologist and as such, of course, became in-
terested in how animals survive and manage to reproduce and even
manage to improve themselves. Very soon it became clear to me that
behavior is one component in the functional systems by which animals
jmanage this. My work, therefore, has involved trying to find out how
behavior is organized in different animals, how its effects aid survival,
and how behavior has evolved in relation to the whole animal. This
zoological science of animal behavior is usually called "ethology" in
Europe. I should like to say that my colleagues and I do not consider

184 • ISSUES IN EVOLUTION

ethology just the result of talking about releasers and imprinting but
would rather define it more widely and say that ethology aims at being
a biological science of animal behavior.

Now this, we realize, is an extremely tall order. I remember that
Dobzhansky emphasized how much we do not know. Without sound-
ing too pessimistic, I wish to emphasize that ethologists more than
agree with him; for our situation, we very strongly feel, is still worse:
very often we do not even know what it is that we wish to find out.
Ethology is struggling to become a biological science. That may sound
pessimistic and perhaps even defeatist; but I think it is necessary to
dampen our own sometimes rash enthusiasm, which has played tricks
on us in the past.

We do know that the intact animal in its natural surroundings is
a hugely complex system. We feel very strongly the need for analysis, ,
and we realize more and more that this analysis has only just begun,
that our subject matter is extremely complex even in so-called very
simple animals. In that respect, of course, ethology is far behind mor-
phology. The study of evolution has often used morphological criteria.
When we wish to use behavioral criteria, we feel we are lagging far
behind, just because we have not yet analyzed these systems as fully
as the morphologists have theirs. In this panel with so many different i
people, it may be difficult to communicate. We speak very different I
languages; that will be clear in the course of the discussion. From my/
side, I shall try to overcome this diflSculty and shall not be too precise j
or too pedantic in asking for an operational definition each time.

Gerard: I began my career primarily as a neurochemist and neuro-
physiologist and have drifted over into being a neurophysiologist and
a behavioral scientist. I am concerned with getting inside that blacks
box. We put electrodes into brains to stimulate the nerve cells and
see what happens — chemically, electrically, behaviorally. We give
animals and people. drugs and make similar observations. The elec-
trodes in particular brain regions also pick up electrical activity that
accompanies neuron functions. This is short-circuiting the system from
input and sensation to output and action of some kind. Therefore,
physiologists are really getting inside the stimulus-response problem.

Our first topic for discussion is the subjective and the objective and
the problems of methodology.

Tinbergen: We have no direct historical record of behavior, and
therefore we have to compare. Comparing animals with other animals
is, in principle, relatively easy, because we can learn from the experi-
ences of comparative anatomy, which was at least a hundred years
ahead of us. But when comparing animal with human behavior, we

PANEL FOUR: THE EVOLUTION OF MIND • 755

run into great difficulties. And again I feel I have to strike a cautionary
note.

We feel there are, in principle, two types of observables when deal-
ing with behavior. One type, which includes the movements of ani-
mals, can be shared by different observers; we can observe animals
together and check each other's observations. The other observables
are the subjective phenomena that coincide with behavior, which we
observe, each of us, in ourselves; and these are, by definition, observ-
able only to the subject.

Now projecting ourselves into other human beings is perhaps allow-
able. We all belong to the same species. Projecting ourselves into ani-
mals is often done. People often assume that what they feel when
angry is very similar to what an angry dog feels; although they can-
not directly observe what a dog feels, they guess at it. Of course, such
guessing becomes increasingly difficult, the further removed the animal
is from us. It is very hard to imagine what a starfish feels when it is
angry, if it ever gets angry. Many persons argue that this is a difference
of degree, but many zoologists (and I am one) think that this is a
matter of principle with no compromise possible. We must confine
ourselves to the first type of observables and act on the assumption that
they are determined by preceding events that can be made observable.

I am fully aware that this attitude is no more than a general working
hypothesis. If we can adhere to direct observables and try to apply
the same method as that used in all the other biological sciences, then
we shall see whether this hypothesis works. That is our attitude and,
I feel, the only attitude possible. Of course, this makes it very difficult
to communicate with those who study human behavior. Some may say
our view is very narrow. All right, it is narrow; but we feel we must
recognize that science is a limited occupation and is only one way of
meeting nature.

Our discussion will often be worded in language into which many
persons (and I am among these) may read subjective connotations.
I feel that it is fruitless to try, every time, to translate our words into
operational language, because we should lose a great deal of time
quibbling about words. My own difficulty, for instance, begins with
the title of this panel: "Evolution of Mind." I would rather speak of
the evolution of behavior; but I won't quibble about it; we each attach
our own meaning to the same words.

Brosin: I mentioned earlier that in dealing with human beings in
distress the psychiatrist and psychoanalyst must work with the material
and the problems that confront them. Such data consist largely of the
so-called irrational forces, outside the patient's awareness, which are

I

186 • ISSUES IN EVOLUTION

often called "unconscious" and "preconscious" activities. There is
much reason to beUeve that these forces are related to the animal-man
referred to at the close of Panel Three yesterday by Rensch and Wad-
dinaton and to the concept of a primary process developed by Freud.
The clinical manifestation of various types of disorientation— leav-
ma aside, for the moment, toxic and organic disease of the central
ne'rvous system and such phenomena as delusions, sensory hallucina-
tions, and motor distortion— can now be much better understood by
means of the concepts and methods of Freud, the experimental work
of Hilgard and others in hypnosis, the LSD-25 series, the sensory depri-
vation^ studies initiated by Donald Hebb and John Lilly (and now
there are a half-dozen good workers, including Solomon and others,
following upon these), and research on the subliminal stimuli, in-
cluding Charles Fisher's studies of perception and dreams.

The'se recent studies, supplemented by film and tape, provide nev/
data and methods relating to the meaningfulness of human interaction
and the intense pressures upon the organism, which have verified or
even surpassed our expectations.

It does not reflect upon the dignity of man to show how closely he is
related to his animal cousins, if we recall that at the same time he is
indeed a most remarkable creature, with practically unlimited capaci-
ties for present and future accomplishments.

Huxley: I am afraid I disagree with Tinbergen. I very much wel-
comed the choice of this title for our panel because it stresses the im-
portance of mind in evolution. I would remind you that Darwin, who
really founded the science of ethology with his book The Expression
of the Emotions in Man and Animals, was perfectly clear that it was
proper to speak of the subjective factor in animals — in this case, the
emotions — and I am quite sure he was right. Of course, it is clear
that the actual study of behavior must begin on a purely behaviorist
level. We interpret our friends' behavior in terms of what we think
are their mental activities; but our interpretation is always based on
detectable sensory signs of one sort or another. In any case, interpreta-
tion in mental terms is the essence of what we do. Animals, too, have
directly observable modes of behavior and deducible mental attributes.
As a scientist, one must infer the existence of qualitative or subjective
properties in the behavior of subhuman animals. Many lower verte-
brates, such as fish and reptiles, react quite distinctively to radiations
of different wave lengths, which give us the sensations of red and
blue. I interpret such reactions as indicating that each of these animals
subjectively experiences some qualitative differences in its sensations,
and I assert that we must so interpret them.

Tinbergen: I know we have been compared to people wearing

PANEL FOUR: THE EVOLUTION OF MIND ■ 187

monochromatic glasses who stand in front of a painting by Rem-
brandt and miss the most important part of the picture. But I don't
think it would be very useful to spend much time on this point. I shall
just say that I disagree. When Huxley says we can deduce something
about subjective phenomena, I think he uses "deducing" in the sense
of "guessing."

Huxley: But from my behavior you would deduce that I see some
difference in color between this carpet and your clothes?

Tinbergen: Right there we are in the middle of semantic diffi-
culties.

Huxley: That is to evade what to me is an obvious fact.

Tinbergen: It is an obvious fact to you, the subject who sees it; it
is not an obvious fact to me. The obvious fact to me is that you react
differently to the two colors and that you tell me so, which is part of
your reaction.

Huxley: I must say I disagree with you. I think we have to believe
that animals do perceive some difference of quality in colors, for in-
stance.

Gerard: But do you call this a belief, or do you call it a fact?

Huxley: I think we have to beUeve that it is a fact, as we have to
do with many other scientific conclusions.

Gerard: The problem, as I see it, is this: in an organism, some ante-
cedent state, which we see externally as material and subjectively per-
ceive as conscious awareness, is followed by a like consequent state.
If we recognize and describe the antecedent state in terms of physical
aspects and the subsequent state in terms of subjective aspects, we are
likely to make such a statement as "ether produces unconsciousness."
But this is just a shorthand and really is not correct. The question I
should like to throw back at you, Huxley, is this: Granting the adap-
tive value of behavior, what is the evolutionary value of awareness?
Why is it adaptive for organisms to be aware of the world and them-
selves? I have never been able to answer that to my satisfaction.

Huxley: What I did not get across is this: I think we shall never
be able to understand this. We have to accept this — to me — mysterious
fact of difference in quality of sensation and other subjective phe-
nomena as an irreducible fact. But I think we can quite properly de-
duce that it appeared during the course of evolution and that it was
of value.

I don't see how one can interpret some of the later stages of evolu-
tion without such an assumption. In our own case, for instance, how
can you possibly interpret the fact that painters paint pictures and that
people like to look at them, unless you believe that the basis of these
colored pictures was somehow present in prehuman ancestors?

L

188 • ISSUES IN EVOLUTION

Gerard: Perhaps this is a good time to leave an unanswerable topic.
I don't think any of us has the remotest idea why subjective awareness
developed. It is not a silly question to ask whether subjective experi-
ence may be arising in computers — or what it is in paramecia or leuco-
cytes.

I think we should take a moment for the problem of the quantita-
tive and/or the pattern aspect of the information with which we deal.

Hilgard: There is no need to elaborate on the obvious advantages
of mathematics to science for giving systematic formulations precision,
economy, and elegance.

A point raised last year by the historian Charles Gillespie intrigued
me. This was the difference in quantitative impUcations between the
theories of Darwin and those of Lamarck. Gillespie pointed out that
the common cliche of the distinction between these — inheritance of
acquired characters — is really not nearly so fundamental as other
differences in their approaches. The fact that Darwin dealt with a mass
of concrete relationships laid the ground for eventual quantification,
so it was very easy for evolutionary theory to assimilate Mendelianism
and population dynamics. Even though Darwin did not use mathe-
matics, his way of thinking in concrete terms made possible counting
and developing probabilities, and so on.

An interesting by-product of this, which I haven't time to go into,
is that if one traces the history of the introduction of mathematics into
my own field, psychology, one finds that model-building in learning
and correlational techniques and the like come through persons in-
fluenced by Darwin. An interesting philosophical point here is that
there is a tendency toward the quantitative in any kind of objective
thinking of the kind that Tinbergen is proposing.

Whether we lose something by this is, of course, a problem of the
appropriateness of mathematics. It is quite as possible to be misled by
mathematics as by any other tool; but it does sometimes help us to
think clearly. Since mathematics makes us communicate effectively,
I suppose we shall see an increasing trend toward its use.

I am sure that part of the quarrel between the objectivists and the
subjectivists is solely on this ground of whether or not we can get a
systematic and unambiguous communication of what we mean; and
mathematics signifies that we have done this. I think that with some
sophistication and by keeping our data or our data language objective,
we can still make inferences like those Huxley wants us to make. My
own reason for working on such borderline states as hypnosis is actu- •
ally to see whether some such thing can be done.

Huxley: Wouldn't you say that, besides his quantitative compara- •
Uve study, Darwm was always thinking in terms of patterns of organi-

PANEL FOUR: THE EVOLUTION OF MIND • 759

zation? He often used the word "higher" against "lower" organisms. I
should have thought this to be an equally important contribution. It is
very difficult to mathematize patterns of organization. We shall have
to eventually, but meanwhile we have to make do with thinking in
terms of patterns. And I would remind you that the ethologists have
discovered that sign stimuli consist of distinctive patterns.

Brosin: I would support the general position that we must have
qualitative data and patterning before we can quantify. We are in a
pre-Darwinian state of exploration.

Gerard: I think we all agree. But I should like to take exception
to calling non-quantitative "non-mathematical." With the possible
exceptions of geometry and the theory of numbers, the development
of the calculus and differential equations and other mathematics of
quantitative difference came before the mathematics of relation or
pattern, which are so new and exciting today. I think it was partly
because the tools were not available and partly because it is ac-
tually harder to understand pattern than to measure amount that
biology and even more the social sciences are behind the physical
sciences. Only now are we beginning to enter the exciting period of
being able to make rigorous statements — not necessarily quantitative
ones — about the phenomena with which they deal.

The panel is now ready to discuss the evolution of behavior and
what it had to do with mind's evolving.

Tinbergen: First, a few general words on what we can say about
the evolution of behavior. Without a direct historical record, we are
confined to indirect methods. (A few minute steps in microevolution
can be studied in the laboratory, and with behavior a start is just being
made; but the results are so scattered and so few that we can disregard
them for the moment. ) Of these indirect methods, the most fruitful is,
of course, comparison of contemporary forms. Now this comparison
is of two types. First is a kind of macrocomparison based on the
"ladder-of-life" concept that assumes we can arrange animals in lower
and higher, or less and more complex, series and that, by reviewing
these, we get some idea of general trends in behavioral evolution. The
second method we could call "microcomparison." By comparing very
closely related species, we try to get an impression in exactly the same
way that an impression of adaptive radiation within a group was ac-
quired in comparative anatomy, acting on the assumption that the
animals compared are really closely related and have a common an-
cestor. Therefore, what we see at present must be the result of diver-
gence.

Now, in macrocomparison, a few things have become clear and are
almost commonplace. In the course of evolution of life, there has been

190 ■ ISSUES IN EVOLUTION

a development toward more patterned sensory perception, more com-
plicated configurational sensory perception. There has also been a
oeneral trend toward more complicated co-ordinated movement and,
with this, a division of labor among different functional parts of the
nervous system. An individual of higher type has a greater variety of
behavior patterns than we find in more primitive or lower forms. With
the increase in the patterning of sensory reception, we find better spa-
tial orientation. We see an increase in learning capacity. We see at
various points on the evolutionary scale an increase in social interac-
tion, which has become possible through a high degree of complexity.

A number of microcomparative studies are now available, mainly
on closely related groups of birds. The surface-feeding ducks have
been well studied by Lorenz, and some of the songbirds have been ex-
tensively worked on. For the purposes of this panel, it is particularly
unfortunate that this method has not been extended to the primates —
the group in which we are most interested — to the same extent as it
has to other animals, although a beginning is now made toward a con-
centrated and truly biological comparative study of the primates. In
Madison, Harry Harlow is making a beautiful study of monkeys. Many
parties are now in the field. I hear that my colleague John Emlen has
succeeded in approaching gorillas in the field and is using exactly the
same methods as those we have been applying to birds. But the pri-
mates involve an enormously more complicated set of problems than,
say, finches or gulls; and when I consider how long it has taken us to
understand something about adaptive radiation in the gulls, I feel a
far greater effort still is needed with the primates.

Huxley: All those interested in animal behavior are greatly in-
debted to Tinbergen, to Konrad Lorenz, and to their colleagues and
followers. They have illuminated this whole field in a totally new and
exciting way. For instance, in my first piece of work I described and
tried to interpret — largely unsuccessfully — the courtship of the Great
Crested Grebe. Now, thanks to Tinbergen and his colleagues, it has
become comprehensible. They have discovered built-in sign stimuli,
releasing mechanisms, and motor mechanisms and have found that
actual behavior depends on an interaction of different and sometimes
conflicting drives, which I would say presumably have some emotional
complement.

Another important thing they discovered was that in certain types
of conflict or frustration, nervous energy — or whatever you like to
call it — flows out into an irrelevant and non-adaptive activity, which
they called "displacement activity"— Hke sham preening during court-
ship; and this may then be seized on by later evolution as the basis for

PANEL FOUR: THE EVOLUTION OF MIND • 191

some new biologically significant and adaptive function. Then, in
recent years, Tinbergen especially has studied the comparative be-
havior of a related group of animals; and with the gulls, for instance,
he found that behavior that seems quite incomprehensible in one species
becomes comprehensible when you study the whole group com-
paratively.

Hilgard: a few years ago, Tinbergen wrote a book with the word
"instinct" in the title. This is a good word, one used by Darwin; and I
should like him to comment just briefly on that.

Tinbergen: I wanted to avoid that word because I feared we would
end up in semantics again. The main reason that, after having written
a book on the study of instinct, I now don't use the word is that I find
it covers at least four entirely different concepts.

Instinct is sometimes used in the sense of anything that is not learned
and refers to the ontogeny of behavior; it then designates so-called in-
nate behavior, not-learned behavior. As applied to characters, that
dichotomy is no longer very popular, although we can retain it for
influences and for differences between species. This is one use of the
word "instinct," and it refers to an aspect of ontogeny, learned or non-
learned.

But instinct also covers quite a distinct concept that is closer to the
original meaning of the word. That is, is behavior purely reactive, a
response to external changes — or is it driven from within? Instinct
here, I think, means something like driving, urging. This use has noth-
ing to do with the ontogenetic distinction.

We use "instinct" in a third sense, especially in human behavior,
when we say someone put his foot on the brake instinctively. Here
again, we mean something entirely different — "not deliberately" or
"unconsciously" — and refer to a subjective aspect open to our own ob-
servation only.

And then, of course, there is a fourth use of the word, and that was
the way I meant to use it in my earlier writings. In many animals
there are rather separate functional systems, such as the whole mech-
anism responsible for feeding behavior and the entire (largely un-
known) mechanism responsible for sexual behavior. You can call such
a mechanism the "feeding instinct" or the "mating instinct." That is
again an entirely different use. In that sense, all behavior is instinctive,
whether learned or not. This confusion is really the reason I think
that the words "instinct" and "instinctive" are not very useful, even
if every time you use them you put in a little footnote, saying "I mean
this or that."

Huxley: The word can still be very useful. I remember when Kon-

192 • ISSUES IN EVOLUTION

rad Lorenz came back from America after a great dispute with pro-
ponents of the view that learning is all-important in behavior, he said,
"I think I have taken some of the stink out of instinct."

Gerard: Hilgard, are you content with this position, or do you wish
to pursue the point?

Hilgard: I am content.

Gerard: I think that, as Tinbergen said, this is purely a matter of
a convenient term to epitomize a series of phenomena. The neuro-
physiologist finds different parts of the nervous system that actively
lead to a kind of behavior, which, seen in man or animals, we call
"emotional behavior" — fear or rage or sex or something of that kind.
We can call it "emotional behavior" or "instinctive behavior" if we
know what we are talking about and avoid these mind-behavior mix-
ups.

We are forever faced with anecdotal stories of domesticated ani-
mals or our garden friends doing things that look highly purposive.
There was a paragraph in a recent Reader's Digest about a chap who
kept squirrels from stealing the seeds from his bird-feeding station
by rigging this so that the slightest weight on one side would tip off
the squirrel. It worked for several days, but then the seeds began to
disappear again. Lo and behold, two squirrels were jumping simul-
taneously on the two sides. Now is this realistic? If it is a valid descrip-
tion of a phenomenon, would you use the word "instinctive" in con-
nection with it?

Huxley: I think we should leave these as essentially philosophical!
and semantic problems. We have many concrete and more exciting-
questions to discuss.

Gerard: You don't want to pick it up, Tinbergen?

Tinbergen: No, I agree with Huxley. Let's turn to concrete ques-
tions.

Huxley: I should have thought that, as a result of Lorenz's and:
Tinbergen's work, "instinct" should be used for a rather elaborate
built-in system involving a sensory pattern that can be received, the
internal releasing mechanism that receives it, and the complex motor
pattern that comes out. It is really a definite type of phenomenon, noti
a general category. '

Gerard: Are we all satisfied with this discussion of topic 3 and
ready to move on to 4?

Huxley: I was going to talk about the evolution of color. This
emerges as something new in the world, and the acquisition of color
vision by animals had an effect on subsequent evolution. I think no-
body would disagree that the capacity to distinguish different wave
lengths did lead to the evolution of brightly colored display characters

PANEL FOUR: THE EVOLUTION OF MIND • 193

in fishes, birds, reptiles, and the like — in other words, that had further
evolutionary consequences. Apparently mammals lost most of the ca-
pacity for color vision during their transition from the reptiles, prob-
ably because they were nocturnal and lived underground. In conse-
quence, they do not show any bright colors in their pelage. They
show blacks, browns, yellows, russets, whites, and grays, but not true
reds, greens, or blues. We know the primates have reacquired color
vision, and, as a result, one finds a full range of colors among them,
with greens and blues and true reds coming back, often in all sorts of
funny places — you remember P. G. Wodehouse's definition of the
mandrill as the animal that wears its club colors in the wrong place.
And then, of course, in the human species, this has had important
biological, social, and economic effects, such as the redness of human
lips and the manufacture of lipstick. Thus color vision is the basis of
much of the cosmetic industry.

Tinbergen: Points 3 and 4 list several examples of human behavior
in areas where every one of us has been asking whether we can see
possible precursors in animal behavior. And I thought it would be
well to discuss some of these in more or less concrete terms. I selected
at random the last item mentioned under point 3, "Operating with
values." I think we can mention some interesting examples of animal
behavior that may give just a glimpse of how in animals we can see
possible precursors of this type of behavior in man.

Man is a social animal and shares with many social animals a cer-
tain set of values. That is how we describe these in man; I think in
animals we could call them tendencies to behave or not to behave in
a certain way; to behave or to inhibit behavior (or misbehave; but
that would be introducing a value, which I won't do). I am thinking
of the remarkable conformity in general behavior shown by many so-
cial animals. In some birds, for instance, there are indications of
special behavior patterns, whose function is to bring an abnormally
behaving individual back into normality. This has been reported in
social birds, for instance. When a bird behaves very abnormally, fellow
members of the group may attack it, and the reaction of the attacked
bird is to come back into the flock and be inconspicuous. When one
approaches this problem as a zoologist, one begins to wonder about
the functions of certain human behavior patterns. One can no longer
doubt that we have something similar; and we even have an intensity
scale of this kind of action. When a person behaves abnormally, we
begin by laughing at him — incidentally, laughing together at another
person ties the two who are laughing very closely together — which is
a very strong stimulus and makes the abnormally behaving individual

194 ■ ISSUES IN EVOLUTION

want to come back into normality, to rejoin the group. If laughing
at him does not work, we "send him to Coventry." That is a still
stronger stimulus. It is worse to be sent to Coventry than to be laughed
at. If this doesn't help, you use open aggression. In our civilized so-
ciety, of course, aggression takes a very mild and non-mechanical
form, but still it is very much there, and the response of the individual,
which makes him want to disappear in the crowd — in other words, to
behave like the others — is very strong. I think if we compare these gen-
eral social devices in behavior in man and in other social animals, we
may find a number of such precursors — possible precursors. Of course,
I am speaking of functionally similar things — of analogies.

Brosin: May I ask a question about your ranking of the types of
behavior? Curiously, you consider direct aggression and assault a
more severe method of correcting unconventional behavior than send-
ing to Coventry. Actually, both personal observation and the com-
munication theory of Sapir and Bloomfield that I mentioned earher
indicate that one of the worst things that can happen to one, and one
of the quickest ways of dehumanizing a person and getting quick re-
gression down to the prmiitive, is to send him to Coventry or otherwise
isolate him.

Tinbergen: The scale of functions may have to be revised. I was
just giving a concrete illustration of the kind of comparison that might
be useful. Sendmg to Coventry might be worse than aggression, I
admit.

Huxley: Do you ever find that higher social animals are sent to
Coventry or sent out of the herd?

Tinbergen: Sent out, yes; but this is done by aggression. You re-
member Goethe's paper on birds. I don't, offhand, know of any animal
equivalent of sending to Coventry.

Hallowell: There again the primates might be useful.

Gerard: I was much impressed by the point Leakey made yester-
day, that in times of severe drought territoriality is abrogated. It struck
me that this looked like a real value judgment. Would vou agree with
that? ^ ^ ^

Tinbergen: There are comparable observations on social birds
who live in flocks in winter. It has been reported of rooks that there is
a regulatory mechanism of the connection between hunger and ag-
gression. When mildly deprived, they will fight each other over food.
When they are very much deprived, under conditions of extreme cold
and extreme starvation, all aggression suddenly stops. I think this
must mean that in these two circumstances selection has put a premium
on two different things.

Hilgard: "Value" is used here in the sense of regulatory social

PANEL FOUR: THE EVOLUTION OF MIND ■ 195

values, but it is one of those words that cover a great deal. One can
study preferences as well as discrimination. For example, besides
color discrimination, one can find a sort of primitive aesthetics. Rensch
has reported that some of his monkeys prefer to string beads of certain
colors rather than other colors. It is not just a matter of whether they
can tell them apart. Here at the University of Chicago, Eckhard Hess
is experimenting with changing the preference of chicks for different
colors. So one can see other kinds of continuity between animals and
man. I think this is really a fascinating notion, following different
strands in behavior to see how we got the way we are.

Huxley: In this, the Satin Bower Bird is perhaps the most remark-
able of all. Not only do the males prefer blue and reject red objects for
their collections in front of the bowers, but scfoie individuals of the
species paint their bowers deliberately. This is definitely the beginning
of aesthetics.

Tinbergen: Let us take another example. The panel yesterday
called the use of tools very distinct from preparing or making tools.
It is, in a sense, unfortunate that through Wolfgang Kohler's work the
use of tools has been linked with something like insight. It is not the
use of tools as such but the spontaneous individual invention of the
use of tools that Kohler pointed out as being important and "rather
human."

We know several animals that use tools in the fullest sense of the
word. One is the Galapagos finch, which lives rather like a wood-
pecker, but, instead of having developed the woodpecker's bill, it uses
the spine of a cactus to probe in cracks and get at insects. That is the
use of a tool in the fullest sense of the word. But all individuals of the
population, as far as is known, do that. Unfortunately, we don't know
how it develops in ontogeny, but I think we can make a pretty good
guess that this is not learned behavior. Another famous example is
the sea otter, which carries a stone on its stomach, and when it has got
hold of a mussel, it will float on its back and hammer the mussel against
the stone to crack it. That, I think, is by all definitions the use of a
tool. But again, the whole population does it, and again we don't know
whether they learn this or not.

Hallowell: Anthropologists discovered long ago that instinct —
at least in one of the definitions mentioned by Tinbergen — was of
little use as an explanatory principle in the study of human societies
and cultures. I think everyone knows this. What anthropologists call
"culture" is assumed to be non-instinctive, to be the consequence of
individual learning and the social transmission of learned behavior
through symbolic mediation. No formal definition of culture is needed
here, but I should like to touch on a couple of other points.

196 ' ISSUES IN EVOLUTION

First is the relation of learning and the transmission of behavior
patterns and thought in human groups to the question of values. It
may be and very likely is important to consider values in evolutionary
perspective, but it seems to me that it would be one of the most diffi-
cult concepts to deal with in this way. At the primate level, to say
nothing of animals other than primates, "value" in relation to the be-
havior of individuals certainly might be conceived to have some rela-
tion to group survival. One of the illustrations Tinbergen mentioned
might concern group survival.

Besides group survival in the biological sense, the human level in-
volves survival of sociocultural systems. The survival of these systems
depends on the socialization process, learning by individuals, and
interiorization of traditional values, which then function in relation
to goals in the society but, at the same time, from a psychological
point of view, permit the individual to be very deeply identified with
the values of his cultural system. This has a double aspect. There is
survival in the biological sense, because from an institutional point
of view — the economic system, the family, and so on — the biological
survival of individuals is secured; but at the same time the sociocul-
tural system becomes an ongoing concern.

As for the tool problem, aside from the differentiation between
tool using and tool making, I see a crucial question in the actual psy-
chological processes involved in what has sometimes been called tool
making among chimpanzees. I came across a statement by Nissen
that the case in which the chimpanzee Sultan actually put two sticks
together was, in fact, a unique observation. In other words, the in-
ventive aspect would seem to be less prominent.

I wanted to link this question of invention by primates with the
emphasis so frequently given to the perpetuation of sociocultural sys-
tems through learning, because undoubtedly we have parallels here
to primates and to other animals. It seems that man has psychological
potentialities, due to psychological reorganization of the hominids
somewhere along the line, which permit perpetuation through learn-
ing and social sanctions of cultural values and a cultural pattern and
which also provide potentialities for cultural readjustment and change
through invention and discovery. This, it seems to me, is very impor-
tant to emphasize. The very fact that culture patterns are differentiated
so widely in Homo sapiens is in itself evidence of this. In other words,
although we can and do speak of culture in a generic sense and while
there are certain universal aspects of culture, in concrete and in his-
torical terms, culture in man is not actually species-specific.

Gerard: Tinbergen, do you think of any clear examples of inven-
tion, sanctions, or social transmission of knowledge in the subhuman
animal?

PANEL FOUR: THE EVOLUTION OF MIND ■ 197

Tinbergen: As many of you may know, titmice in Britain had
developed a habit of opening milk bottles left at the front door. From
a study of the spread of this habit through Britain, James Fisher and
Robert Hinde have concluded that it must have originated in many dif-
ferent places. From these centers, it must have spread through the
population, partly through tits of the same generation imitating each
other and perhaps partly through transmission from one generation
to another. There is very little doubt that here is an example of a
discovery by birds, and not by only one individual in the population,
but by a number, yet a limited number. It is now so widespread that
most houses have a metal cup or a stone ready for the milkman to
put on top of the bottles. It is a rare invention, and we know few ex-
amples of this; but it does occur.

Huxley: There were several centers of origin from which we have
been able to measure the rate of spread of the habit. There was one
center in the Low Countries.

Gerard: What about the red deer, where the old female in the
group is supposed to pass on knowledge of the terrain?

Tinbergen: I have no information about that.

Huxley: There is a much better example available. Do you remem-
ber the case of the monkeys in Japan, reported at the International
Zoological Congress last year? These monkeys live in troops, each
with its own tradition of food preferences. Every now and then these
will change. And this is very interesting: the change seems always to
be introduced by some naughty young monkey who wants to eat some-
thing different. To start with, his mother spanks him; but if he is
naughty enough and wilful enough, he goes on eating it, and then she
eats it, and then the custom spreads. This is a remarkable example
of a youthful individual initiating psychosocial change — a Prometheus,
as it were, of monkey diet.

Hallowell: It is very interesting that, instead of these new food
habits being accepted by older monkeys, they very often are accepted
first by the younger animals, from whom the older monkeys then
learn. However, Imanishi's use of the terms "culture" and "accultura-
tion" involves a problem we do not have time to discuss here. But, as
I mentioned yesterday, it seems to me that in human evolution, both
social and psychological, we have to conceive of some kind of pre-
adaptive stage. I should prefer to call this "protocultural," because
the life of these animals as compared to man shows qualitative and
quantitative differences. I think in discussing evolutionary problems
we have to be very careful of our terminology.

Critchley: It seems to me that one of the principal gaps in our
understanding of this smooth, orderly progression between the highest
representatives of the Primates and the lowest representatives of Homo

198 • ISSUES IN EVOLUTION

sapiens is the abrupt introduction of language, because, no matter
how vocal an animal is, however rich its repertoire of sounds, it can-
not, strictly speaking, be spoken of as being endowed in the precise
sense of the word with either speech or language. At the very most,
we can use the term "animal communication." At present, there seems
to be a very real distinction between animal communication and
human speech or language.

Gerard: What about a man and a dog interacting?

Critchley: That is capable of a different interpretation altogether.
Somebody has said, rightfully perhaps, that it is easier to translate
thirty pages of Cicero than to understand fully the meaning of a croco-
dile's grunt. The matter of the man and the dog is another story.

I think we can say that the main difference between animals and
man in this respect is that in their system of communication animals
employ signs, whereas man makes use of symbols. That is the big
difference.

Gerard: When a dog sits up and begs for sugar, what is it doing?

Critchley: Making signs.

Gerard: I question that.

Critchley: When we look at the problem, trying to detect the
bridge between animals and man, we can perhaps assert that the right
way would be to look not so much for the beginning of articulation
or the articulate use of symbols as to seek rather the beginnings of
symbolic thought or behavior or a manipulation of symbols in ani-
mals. If we can only descry somewhere in the animal scale the be-
ginnings of these phenomena, perhaps then we might be witnessing
the very earliest precursors of language and then perhaps we can see
things of significance being attached to some inanimate objects out-
side themselves. For example, when we find an ape choosing an ob-
ject — a stone or stick or a piece of rag — carefully setting it aside and
preserving it and then utilizing it as if it were a sort of plaything (not a
tool), then perhaps we are witnessing the beginnings of symbol forma-
tion. Perhaps this is the beginning of symbolic thought. Then, from
the particularization of one single item in the environment to the en-
dowment of this particular item with a name is really only a step. It
is a big step, no doubt; but, anyway, it is the sort of step that we
humans can visualize without too much difficulty.

Tinbergen: What Critchley says is fully borne out by most studies
of animal communication. Ethologists also feel there is an enormous
gap between the very simple "sign language" observed among ani-
mals — of which we know a great deal now — and human speech. Here
again, a study of the primates is needed to fill the gap.

Sign languages in birds and fish, for instance, are all of this type:

PANEL FOUR: THE EVOLUTION OF MIND • 199

They carry a message — "Do this now." They elicit something — "Stop
this now" or "Come here" or "Go away" or, in very rare cases, "Go
there"; and, oddly enough, the best example of that last message is
found in the honeybee. In birds and even in mammals this is extremely
rare — not because they cannot point somewhere, but because it is
so obviously difficult to react to pointing-somewhere (as every dog
owner knows).

Gantt: I should like to go back from the heights to which Critchley
has brought us and mention one or two common characteristics we
see throughout the animal kingdom, parallel, perhaps, to what von
Muralt said earlier about the common transmitters of nervous impulses.

Throughout the animal kingdom, whether we study higher or lower
organisms, we see that if organisms can form any individual condi-
tional reflex at all, they form it at about the same number of repeti-
tions. That is, a worm will learn as quickly as a human being the kind
of things that it can learn. This, of course, has some kind of teleological
basis, because if a worm couldn't learn in two or three attempts, there
would be little purpose in its learning at all; it does not have a very
long schooling period.

I should like to say something about the perversions of our evolu-
tion of behavior and mind. Gerard has used the terms "racial reac-
tions" and "becoming" for what, in more restrictive laboratory lan-
guage, have been called "unconditional" and "conditional reflexes."
Now, as we go up through the animal kingdom, we see that it is not
the speed at which these individual reactions are formed that increases,
but the complexities. As we reach the human level, these reactions
become very complex — the interrelations between the symbols — so
that, as human beings, we have achieved even the possibility of escap-
ing the gravity of the earth. However, in this formation of the com-
plexities there is also a great liability. As we form more and more indi-
vidually acquired responses to certain situations, we find that we do
not have to be very old for this to occur. We become, as it were, a
museum of antiquity, so that, having once formed these responses, it
is very difficult to unform them.

I want to mention one example of this, from the studies I have been
carrying on. In studying the cardiovascular reactions, we have seen
that these form much more quickly than the ordinary conventional
conditional reflexes, such as the movement or the secretion of a gland.
They will ordinarily form after one repetition. That is, to a certain
kind of situation your heart rate and blood pressure will increase. This
increase is learned, is acquired during the life of each individual, and,
once formed, it is very difficult to get rid of. Pavlov has shown that
through the process of extinction you can return an individual to what

200 • ISSUES IN EVOLUTION

seems more or less to be his preconditioning state, and he will seem
to be neutral toward that situation. Hovv'ever, if you follow his cardio-
vascular reactions, you will see that these persist, even though the in-
dividual, when looked at externally, seems to be at rest. By studying
the more internal autonomic responses, we see that he may be very
violently disturbed and that, under certain circumstances, particularly
susceptible individuals can never be returned to their normal condi-
tion. This is what one finds by studying some of the less observable
and autonomic responses, and I think this is one of the chief bases of
our psychopathology and the kind of phenomenon we must look at.
Aside from our marvelous ability for adaptation, we also have to con-
sider this other side — the hazard and the liability that human beings
have because of the special complexities of their possibilities for re-
acting and forming responses to their individual experiences.

VON Muralt: From the point of view of the neurophysiologist, the
integration that occurs in the building-up of the central nervous system
is based on organization, and not on the introduction of qualitatively
new elements into the system. It is the pattern and the development of
pattern, the organization and the working-together, that make the
complexity of the structure. Basically, the elements are always the
same.

Gerard: You are thinking of the higher levels there, aren't you?
As you pointed out, if one starts low enough, there is not even a nerv-
ous system; so the appearance of a nervous system is one mechanism
for improved behavior. Then comes the more rapid conduction in
nerves because messages jump from one break in the insulation to an-
other hole, and so speed up conduction enormously. The receptors
are tremendously increased in sensitivity. The light needed to excite
the eye of a clam, for instance, is 10^ units, and that needed to excite
the eye of a human is 10^ — ten million million times less. Advances at
lower levels are unquestionably related to the improved elements, just
as later radio tubes were better than earlier ones.

But the point von Muralt raised certainly comes in at the beginning
of the vertebrates and probably improves up to the mammals — we
don't really know the facts about this — by better circuits and better
patterns rather than by better units. The later developments of the
radio involved heterodynes, superheterodynes, and improved designs;
similarly, there are impressive developments in the circuitry of the
nervous system.

Some of these have been alluded to. For example, the very existence
of a synapse connecting neurons with one another allows the separa-
tion of input and output, thus dissociating stimulus and response in
time and giving variabihty to their relation. Then, instead of an im-

PANEL FOUR: THE EVOLUTION OF MIND • 201

pulse coming in and going out through a series of neurons and to an
act, it may turn back on itself to form a loop of neurons in which
messages may be trapped and go round and round — the way the con-
traction in a jellyfish bell can be made to go round and round when
started right.

Next, there are the specific so-called feedback mechanisms. Critch-
ley does not like this term, and, as a biologist, I also objected to it
for a long while; but the engineers have had us there, and it has come
into general use. These mechanisms act as a sort of volume control.
A message getting into the nervous system may be too strong for the
circumstances, and feedback cuts down the upward flow of messages.
You have perhaps heard of some recent experiments showing variation
in the size of the response generated in the cat's ear by a click of con-
stant intensity repeated over and over again regularly. If the click has
no special significance to the animal's existence, the response rapidly
decays until it is practically undetectable. This is habituation — just as
you learn to sleep next to the railroad, despite trains rumbling by. Con-
versely, if that same click is made the conditioning signal to indicate
to the animal that it will be shocked, then the response, instead of
decaying, gets much larger. This is obviously a physiological mani-
festation of what the psychologists would call "alertness" or "atten-
tion."

There are many other neurological mechanisms; I can mention only
the direct and the indirect or diffuse system. The diffuse system is
clearly related to the kind of experience we call "emotional" and again
gives the set; the discrete system is associated with the pattern experi-
enced rather than its set or tone. These are some kinds of patterns that
have come into existence in the development and evolution of the
nervous system. They are probably all present by the origin of the
mammals; at least, we have no reason to think that there has been
further improvement along these lines.

What does seem to have come in later — a point that came up in
yesterday's panel — is simply more neurons to do the same things. It is
a very interesting point that more of the same can really lead to a
qualitative difference. It is not just sheer number of neurons; the ele-
phant has a much bigger brain than man, but man is the more in-
telligent.

But, disregarding special masses and uses, in the over-all story it is
nonetheless true that increase in the number of neurons available to
do something seems to increase vastly the skill with which it is done.
The largest area in the cortex that controls motion in man is that asso-
ciated with movements of the tongue, related to the fine manipula-
tions of chewing and particularly to articulation and speech.

202 ' ISSUES IN EVOLUTION

Time lacks to develop this further, but one last point needs men-
tion. There may be (this is still hypothetical) a difference in the
amount of time taken (that is, the amount of activity that has to re-
verberate around in the brain) between the time a message comes in
and the time it has fixed a memory. We have been able to measure
this time as something like fifteen minutes. A blow on the head can
give a lasting amnesia for the preceding minutes; an animal given an
electroshock each time after running a maze shows no progressive
learning if the shock occurs within fifteen minutes after the experi-
ence. This failure is not due to damage by the shock, because if it
is given four hours after the maze running, learning is perfectly good.

Perhaps even learning can be outside the brain. As I said in opening
the panel, RNA molecules may be concerned; and recent work sug-
gests learning in non-neural parts of the body. Flatworms have been
conditioned by a bright light or a sound to turn away before a shock
is given. They are then cut in two. The head regenerates a tail; the tail,
which, as far as we know, has no neurons in it, regenerates a head.
The regenerated-tail flatworm remembers what the whole worm
learned. This is an exciting problem!

We are nearly at the end of the panel, and, rather than attempt a
summary, I am going to ask each member to indicate his vision of the
future.

Brosin: As a clinician, I am sure that we need much more knowl-
edge of the main facets of human relations. More specifically regard-
ing problems of method, there is, first, the problem of the observer
and his effect upon the systems on which he is impinging, including
such phenomena as transference and countertransference. Second,
I should say, is the problem of the barriers to studying such component
systems and larger total systems as reciprocal relations, including the
dirty word "feedback." A third problem is the possible application of
the complementarity principle, enunciated by Niels Bohr and sup-
ported by J. Robert Oppenheimer, to the contradictory data we have
to put up with every day. And, finally, there are the problems brought
up yesterday in Panel Three by Waddington and Rensch: better
methods for maintaining this very nice balance between the forces of
animal-man and the requirements of society or moral conscience; be-
tween the need for stability as exemplified by the verities, and a lively
skepticism and a capacity for accelerated change that will enable us
to survive.

Critchley: Briefly, my expectations of the future are (a) a short-
term hope and (b) a long-term prophecy. My short-term hope is (1)
more data, better documented, better observed, and better studied.

PANEL FOUR: THE EVOLUTION OF MIND ■ 203

and (2) a get-together of pathologists of language with linguists. Up
to now this has not happened, and it must.

My long-term prophecy is that in the remote future the inhabitants
of this earth may possibly use some form of communication other than
words, other than a purely verbal system. If they do not, there will
have to be a vastly improved linguistic system, because at the present
time words are not enough. We have met that fact already today:
four meanings for the word "instinct."

Gantt: I do not want to disguise my interest in survival, which has
been emphasized here. I think increase in knowledge, although very
necessary, will take care of itself because of the highly developed func-
tion of curiosity in human beings. I think we need more studies of
group activities. Not only do we need studies that will enable us to
prevent the individual's getting into pathological conditions — a big
problem at present — but we need more studies of activity between
groups. I think that the future will depend on our success in maintain-
ing a balance between increasing knowledge and our ability to cope
with the results of this increase.

Hallow^ell: In our symposium, nothing has been said about per-
sonality structure. I think that for this evolutionary problem we need
a model, whether Freudian or of some other kind. The use of such a
model is necessary in concrete research. Although the word "mind"
is meaningful and significant in a broader way, for actual concrete
investigations we need such constructs as ego, even if not in the sub-
stantive sense. Heinz Hartmann, for example, has suggested that at the
human level the ego may be conceived to have survival value, since
adaptive functions, which at a lower level are taken care of by in-
stincts, in man become functions of the ego.

Veith: As a historian, of course, I have no aspirations toward
prediction. I agree with Critchley that we shall need many more data
for better knowledge. One point that would interest me very much was
touched on by Hallowell, namely, the rise of self -awareness, of ego-
consciousness, in the human being. Another question, which one day
might be solved by men like Brosin or Tinbergen, is whether the com-
ing into existence of self-awareness might possibly have given rise to
the first maladaptation.

Hilgard: I see a kind of division of labor in the things that need
doing. On the one hand, we need to move toward precision; on the
other hand, we have to be careful that this does not sterilize our in-
vestigations so we do not dare face larger and more difficult problems.
So I suppose one of the things I would urge is a return to more natural-
istic observations of man with considerable freedom; the reintroduc-

204 • ISSUES IN EVOLUTION

tion, for example, of the chapter on "will" into our textbooks. Of
course, this is a very difficult word, but how do people make plans
and fulfil such plans (which, of course, they do all the time)?

We have to be aware of our subject matter and find appropriate
ways of describing it. Because we lack such ways now, we tend to
ignore some of these problems by concentrating on others where
methods are more precise.

One concrete suggestion concerning evolutionary process is that
we might have a somewhat better taxonomy of behavior. In the dis-
cussion of brachiation yesterday, for instance, I thought that this was
not the best kind of behavior term. This is essentially a taxonomic
problem: Would "prehension" (a behavioral term) be any better than
"finger-thumb opposition" (an anatomical one)? A careful examina-
tion of the kinds of threads we could follow if we are following a be-
havioral pattern rather than a morphological one seems to me to
need rather careful work. I think the ethologists are helping us on that.

Huxley: I should like to pick up what Hilgard said. We need much
more observation and analysis of the actual facts of the individual
development of mind in our own species: development of the inte-
riorization of our environment and of its organization and adaptive
types of organization; the investigation of critical periods for learning
languages and other things, for the development of conscience, and
so on. And then the very exciting new idea that Waddington threw
into the discussion yesterday, the idea that the human infant is geneti-
cally equipped with something analogous to an imprinting mechanism
for beliefs, for accepting what he is told. Of course, the beliefs and
ideas afterward have to be corrected by education and experience, but
they are based on some sort of acceptance mechanism.

And then, on a more general line, I hope that more attention will be
paid to what Gerard stressed, that what we are dealing with in the
rise of mind is always connected with the reverberation — a nice word
— of sensory input within a bounded field system before it issues in
motor output. To me, the crucial point is how this bounded field
system of reverberation arises and how it generates consciousness.

VON Muralt: I think that the situation of the neurologists is some-
thing like that of the astronomers. We are beginning to understand a
little bit about the functioning of a single motor unit or a single nerve
cell, and the more we learn, the more we see that we are just at the
beginning of understanding. When we realize that in one gram of
brain substance there are several millions of such interrelated cells, I
think the only attitude we can have toward the future is one of pessi-
mistic courage.

Tinbergen: My views about what I consider most urgent have

PANEL FOUR: THE EVOLUTION OF MIND • 205

come out during the discussion, but I could briefly sum them up
again. I am very much interested in attempts to apply biological con-
cepts and methods to the behavior of animals and of human beings.
I feel that we have merely skimmed the surface. I think we ought to
develop, in both width and depth, the comparative study of closely
related species, especially, of course, the primates. Further, I feel
we ought to give more attention to the survival value of behavioral
aspects, in order to understand what natural selection has done to
behavior. Then, of course, the genetics of behavior must be studied
much more intensely; and, last, the application of artificial natural
selection in the laboratory has been shown to be possible in certain
cases and should be continued on a much larger scale.

Gerard: I would say a word in closing about my own picture of
the future development of the human mind. We hear a great deal of
discussion about man's improving his brain by genetic processes. I
have no doubt that we have enough knowledge to breed for anything
we agreed upon. The trouble is that we don't know what we want to
breed for, and our social institutions do not encourage that sort of
action.

A second way of improvement would be by making maximum use of
the developmental capacities of the nervous system, to which Huxley
just alluded; and I have no doubt from the experimental evidence
that putting more in earlier can develop better patterns of activity.
Whether you can do this later on is very doubtful; but young children
can be taught a lot more than they often are.

A third aspect is that, as man has learned to supplement his muscles
with bulldozers and donkey engines and his sense organs with radar
and photocells, he is now learning to supplement his central decision-
making processes and reasoning processes with other instruments that
have come to be called "computers" — a kind of organism that is
evolving more rapidly than anything else in the world. It is going
to be possible to help our brains with these to a significant degree.

Finally, the most important thing of all, of course, is not the mind
of individual man but the collective mind of collective man. This is
more than just a term, because we are developing organs of society,
such as Hbraries and writing, the modern techniques of reclaiming
knowledge, with "sensory" machines, the punch-card machines that
filter out and organize facts, and so on. These are very powerful tech-
niques and are the beginning of the answer to Critchley's request for
something more than words in the future.

Since the whole magnificent picture of evolution is, after all, the
product of human brains, I cannot beheve that human brains will not
be able to find solutions to the ways of men influencing one another

206 • ISSUES IN EVOLUTION

that are superior to that old, inefficient, and very destructive one of
beating people over the head, whether with clubs or atom bombs. This
is the great hope of the future of the sciences of behavior — that man
will learn to interact effectively. I am more optimistic than my fellow
neurologist.

PANEL FIVE
SOCIAL AND CULTURAL EVOLUTION

Chairmen: Clyde Kluckhohn and Alfred L. Kroeber

Panelists: Robert M. Adams; Edgar Anderson; Sir Julian Huxley;

Hermann J. Muller; Fred Polak; Julian Steward; Leslie A.

White; Gordon R. Willey

Preamble

In Panel Five we deal specifically with those creations of societies of
man which summatively we call "culture." Culture is an extrasomatic
or exosomatic body of products, including languages and systems of
ideas or sentiments, or, viewed diachronically, a flow of such products.
The term "culture" is used here as the most widely employed with the
broadest meaning in anthropology and other sciences of human social-
ized behavior. Culture has structure, patterns, and functions. It chan-
nels human activities. While always the product of man, past or pres-
ent, it also affects and inescapably influences man, especially when
men are congregated in societies.

The concept of the evolution of culture challenges us to recognize
or perceive the nature of order in cultural change and to formulate
principles which systematize such order. The principle of evolution as
applied to culture followed in the wake of the idea of human progress
which developed in western Europe in the seventeenth century, spread
widely in the eighteenth, and became an almost universal a priori
principle and sentiment in the nineteenth. This idea of progress, there-
fore, definitely antedated the recognition of both the concept of cul-
ture and the principle of evolution. It must be assumed to have had a
heavy influence in aiding acceptance of the principle of evolution
after 1859. After about 1890 it began to be recognized in anthropo-
logical science that the assumption of inherent human progress was
mainly an a priori sentiment with a posteriori selective shoring-up. The
result was first an "antievolutionary" reaction, really directed against
ethnocentrism, and then a gradual effort (Childe, Redfield) at em-

207

208 • ISSUES IN EVOLUTION

pirical determination of definable progress comparable to "grades"
in biological evolution.

Points for Discussion

1. In a consideration of cultural evolution we are concerned with
past, continuing, and future interactions of societies or individuals
under the influence of culture. At the same time, we are con-
cerned with the interrelations between cultural evolution, on the
one hand, and both the biological evolution of man and other
organisms and the changing physical environment, on the other.

2. The unique abiUty of human beings to produce culture is due to
their special faculty of symbolizaition, which produces both lan-
guage and the probably related ability to abstract, to superadd
concepts to percepts. These faculties allow knowledge and ideas
to be communicated, stored, and accumulated. The consequence
is that culture, like speech, is always acquired by learning. It is
not congenital. This is a great advantage, allowing much more
rapid adaptation to environment and more rapid evolutionary ad-
vance.

3. In man, biological evolution through gene shuffling, selection,
and mutation can go on simultaneously with cultural evolution,
and they are both operative. But cultural evolution has become

— much the more effective and dominant. The time seems past when
biological evolution, in any single species other than man or in
all of them combined, could rival or surpass man's cultural evo-
lution. The opposite seems already to be true.

4. As far as we know now, cultural evolution in Homo sapiens is
essentially independent of gene differences between human sub-
groups or races. In that respect, the courses of organic and of
cultural evolution are different.

5. While involving reticulate aspects, especially among the lower
taxa, biological evolution generally takes the form of a branching
tree made up of diverging lines of descent. The lines of cultural
descent may run parallel, or they may diverge through innova-
tion, isolation, adaptation to a local environment, etc., but at the
same time they converge and commingle through contact, spread,
diffusion, communication. Cultural evolution is different from
biological evolution, in that aspects of culture— ideas, techniques,
institutions— can be almost indefinitely combined and hybridized,
regardless of the disshnilarities between the cultures that produced
them.

6. Cultural accumulation occurs in economy, technology, and sci-
ence. Small-unit social groupings such as the family tend to per-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 209

sist, while larger political integrations tend to be superadded and
to dominate. In other fields, especially the styHstic aspects of cul-
ture, successful creative efforts come mostly in non-cumulative
intermittent bursts or pulses.

7. On account of their constant interflow, cultural phenomena allow
cross-cutting classification into equally valid ( 1 ) historical units
of cultures ("civilizations") or (2) abstracted "levels of integra-
tion" (Steward). The civilizations correspond imperfectly to bio-
logical clades or taxa; both represent sequences of historic con-
tinuity, and both show potentialities for survival value and fur-
ther advancement. Sociocultural levels or stages correspond
roughly to the biological "grades" attained by innovating ana-
genetic improvement and maintained by stasigenetic persistence.

8. Organic evolution is always continuous, as are cultural evolution
and human history. But it is punctuated by relatively brief periods
of crucial change, in which previously non-dominant forms of life
achieve an evolutionary breakthrough to a new level or grade of
organization and capacities. This new grade then undergoes rapid
and intensive adaptive radiation and attains dominance, main-
tained thereafter with lessened change. Examples are the taking-
over of dominance from Triassic-Cretaceous reptiles by warm-
blooded mammals and birds at the beginning of the Tertiary and
also the breakthrough of cultural evolution with man in the
Pleistocene.

9. Within human cultural evolution several corresponding major
critical breakthroughs (sometimes called "revolutions" in pre-
history and history) have been discerned in the accumulating em-
pirical evidence. These are ( 1 ) food production, beginning grad-
ually about 7000 B.C.; (2) a syndrome centering around 3000
B.C., in which writing, metallurgy, urbanization, and political ^
structures were first evolved; (3) from about 600 B.C., religions
organized both doctrinally and institutionally; (4) beginning
about A.D. 1 600, a level or grade of civilization characterized by
the rapid and progressive development of science, technology,
invention, industry, and wealth.

10. In the light of present evidence, these respective advances con-
cerned primarily subsistence in stage 1, general civilization in 2,
religion in 3, and secular activities in 4, with definite, perhaps
reactive, change of emphasis or direction in each surge as com-
pared with the preceding one. A world-wide spread (roughly
corresponding to "adaptive radiation") in the fourth stage is ap-
parently still taking place. When it shall have covered our planet,
a degree of temporary stabilization may occur.

1 1 . While adaptation on the part of the organism has been strongly

210 • ISSUES IN EVOLUTION

Stressed as a primary factor and result in the evolution of ani-
mals and plants, both by Darwin and by modern evolutionists,
it has been a much smaller consideration in the exosomatic physi-
cal and organic environment through selection. The function of
culture is not only to adapt man to his environment but also to
adapt man's environment to himself by suitably modifying it.

12. The basic and primal inventions of culture — fire, clothing, shelter
and constructions, tools and weapons, food preparation, cook-
ing and cooking utensils, storage of surplus food and later food
production by farming and herding — all these modify, change,
or abolish difficulties existing in the natural environment by
(partly) substituting an artificial (man-made) environment of
artifacts. This indispensable material basis of human culture is
subsumed under the term "technology" and remains the chief
means of subjugating environment as well as adapting to it.

13. The result of points 11 and 12 is that most anthropologists and
students of culture have been less concerned with adaptation and
its relentless flow than have biologists. They deal with change,
advance, accumulation, and interpersonal and intersocietal proc-
esses, which they have often assumed to be non-adaptive. Their
concerns are usually microdynamic. Even the term "evolution"
tends to be avoided, partly through persisting reaction against the
speculative pseudo-evolutionistic excesses of anthropologists in
the immediate post- 1859 period. As to the macrodynamics'^of cul-
tural evolution, its causes and principles, and its interrelations
with biological evolution, there is as yet no general agreement.
For the near future this subject needs careful research. This is
necessary as a basis for any attempt to predict or control the di-
rection of cultural evolution.

14. The nearest counterpart in anthropology and the social sciences
to genetic evolutionary science appears to be carried on mainly
under the name of "culture history" (including prehistory) and
is naturalistic, empirical, hohstic, seeking continuities and con-
nections rather than phenomenal identities or "regularities" and
yet ready to accept such "regularities" and punctuating cultural
"revolutions" insofar as these are demonstrable. Such knowledge
is important for gaining a timely and adequate insight into the
processes forming the future.

15. The very historization of understanding in science which our
present fourth critical stage of innovation has brought with it in-
volves greater awareness of evolution and of the future as well
as the past. This awareness will no doubt produce efforts to di-
rect the course of evolution. No precedent exists for predicting
what success such efforts may have.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 211

Whether the next grade be attained automatically or partly by
willed planning, the orientation and kind of its innovations con-
stitute a most significant problem. The advances of modern sci-
ence and technology in gaining deeper understanding of physical,
biological, and cultural phenomena and in devising means of
controlling them place in man's hands tools of unprecedented
power. The use of these with insufficient foresight could have
undesirable and even disastrous biological and cultural conse-
quences. Conversely, their use with foresight would offer possi-
bilities of human evolution both cultural and biological far ex-
ceeding those of the past. What happens in these fields will de-
pend increasingly upon the nature of the goals set and the means
employed, provided that men succeed in extending wisdom and
conscience into this sphere. Here is an enormous new field for
a rethinking of the problems of human life and of life in general
from the bottom up, taking into consideration everything that the
past has taught us.

The Discussion

Kluckhohn: There have been many leads into this panel from the
others. Simpson reminded us that cultural evolution is also a bio-
logical adaptation. Waddington said that man has invented for him-
self a new evolutionary system, since writing, which is one important
way of preserving and transmitting culture, has functions analo-
gous to those of the DNA chain. Huxley suggested that the course of
cultural evolution centers on a kind of natural selection among a
procession of ideas that are successful for longer or shorter periods.
Everyone concedes that cultural evolution is an extension to biological
evolution, yet different from it. But different to what degree and in
what respects? To what extent does either process involve or con-
strain or channel the other? Such propositions are immensely debat-
able. Let us return, for example, to Waddington's statement that the
new system for the transmission of information, depending on the
printed page, implied a new system of evolution. I myself like that
formulation, but I am not sure that all my colleagues accept it.

It should be underlined that, while all the propositions in our agenda
have some evidence or authority behind them and a number of them
are regarded by all members of this panel as empirically established,
others are disputed. The weighting and phrasing of still other issues
are arguable. Some of these disagreements and shadings will emerge
in the discussion.

Over and above questions about the trend of the facts and the in-
terpretation of such trends, there remains the vexing question whether

212 ■ ISSUES IN EVOLUTION

the concepts of contemporary anthropology are adequate for valid
analysis. For instance, do we have sound taxonomic bases for a cul-
tural typology, Mayr has rightly said that you can't talk about dy-
namic flow until you can recognize types. There are other crucial prob-
lems. How much transformation occurs in social change — how much
abrupt alteration of cultural principles?

But enough of these preliminary remarks. I shall now ask Kroeber
to initiate the consideration of point one of the agenda:

In a consideration of cultural evolution we are concerned
with past, continuing, and future interactions of societies or
individuals under the influence of culture. At the same time,
we are concerned with the interrelations between cultural
evolution, on the one hand, and both the biological evolution
of man and other organisms and the changing physical en-
vironment, on the other.

In so doing, he will necessarily explicate some parts of the Pre-
amble.

Kroeber: While the word "evolution" is applied to life, to the
earth, to the cosmos, the usual term in human affairs is "history."
I submit that, except for certain overtones of connotation, the two^
words mean the same thing, namely, long-term change.

Even more important than Darwin's establishing that change ini
life-forms occurs, and through natural selection, is the fact that, until
1859, all sciences were essentially static. It was Darwin who triggered
the sciences dealing with the earth, life, and culture into becoming
more macrodynamic or historic.

The first broad and influential idea of gradualistic development in
any domain, though still a prescientific and semiphilosophical notion,
was the assumption of human social progress. This idea seemingly
originated in France, two hundred years before Darwin, and spread
to England, western Europe, and America. It had built up a tremen-
dous pressure of public opinion behind the dam of behef in non-change
of a static world, which dogma and a habituated static science had
jointly long maintained. This pressure helped enlarge Darwin's great,
but specifically biological, discovery into a still greater breakthrough
affecting all science.

It was from thinking socially about culture, where it is an actual
process, that the idea of transmission of acquired characters was er-
roneously introduced into biology by Lamarck, Herbert Spencer, and
others.

It is worthy of note that the first phylogeny supported by evidence,
that of the Indo-European language family, was established in the
field of the so-cafled humanities seventy years before Darwin.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 213

Huxley: I entirely agree with Kroeber. We know there is com-
plete continuity between man and prehuman animals; we also know
that man is a very unusual and, indeed, unique kind of animal. This
transition from animal to unique animal meant crossing a threshold
to a new kind or phase of evolution, which may be called "cultural"
or "human" or "psychosocial." The panel yesterday pointed out that
it took at least a quarter of a million years to pass this threshold. The
transition led into a new phase of evolution, with new mechanisms
of transmission and transformation. As Kroeber said, the cumulative
transmission of experience is a second method of inheritance, acting
like an inheritance of acquired characters.

We have, therefore, new methods of directing change. The process
of natural selection is teleonomic, to use Pittendrigh's useful term. It
directs change toward better chances of survival — which include
higher organization and more efficient physiological functions — but
without conscious purpose or planning. In man we have the begin-
ning of a process that is, in the strict sense of the word, teleological,
since purpose — consciously or unconsciously, but, in any case, sub-
jectively, wanting to do something that is envisaged in the future —
comes in. Thus you have a changeover from a teleonomic to a strictly
teleological mechanism. And selection is exercised, not mainly by
the differential survival of variants (to use the rather forbidding
terminology of Panel Two), not by natural selection, but by — well,
the anthropologists will have to find out what is the right term; per-
haps telic selection would serve. For the present, I shall merely call
it "psychosocial selection." This implies that there is some kind of
competition for survival and further development among ideas, social
systems, and types of culture. As a result of this new mechanism, the
whole process moves much faster. Instead of reckoning major ad-
vance in tens of millions of years, we reckon it in centuries.

As a matter of fact, there is another crucial new consequence of
the new methods of psychosocial evolution. If averaged out over the
whole two and one-half billion years of biological evolution, the rate
of evolution would be more or less uniform, going up and down, but
always around a certain average rate. In psychosocial evolution it is
quite clear that, at least in the last few millennia and especially in the
last few centuries, there has been an acceleration instead of a more
or less uniform rate.

As a result of all these differences, the products of psychosocial
evolution are totally new and unlike anything produced by biological
evolution. They are cultural products, like science, rehgion, art, and
law. I thought Waddington's contribution to the discussion in Panel
Three was extremely relevant. He pointed out that certain new built-in

214 ■ ISSUES IN EVOLUTION

mechanisms of mind were desirable and, indeed, necessary for this
sort of evolution to work: especially a built-in acceptability of what
we are told by our parents and our elders and betters. Later, of course,
we have to be educated or educate ourselves out of accepting such
ideas and beliefs as absolute. But our beliefs and values are originally
based on this quite new method of transmission.

Muller: As stated in the discussion of man as an organism, bio-
logical evolution laid a genetic basis for those faculties of body and
mind that were necessary before culture could develop. Among these
were adroit hands, general intelligence, a social co-operative nature,
and, more specifically, symbolizing faculties — urges to vocalize, to
communicate, and to imitate — and facility in manipulation. Not only
did the use of these faculties actually result in the gradual accumula-
tion of primitive culture, but, reciprocally, the modes of life opened
up by culture gave increasing opportunity for the effective exercise
of these very faculties and so bestowed an increasing relative advantage
in the struggle for existence on those individuals, families, and groups
of famihes in which these faculties were better developed. That is,
by putting a premium on these faculties, culture intensified the natural
selection whereby their genetic basis was still further improved. Thus
in the hominids and hominines there must, on the whole, have been
a positive feedback lasting for a long time, whereby cultural evolu-
tion aided biological evolution and vice versa.

However, as culture advanced to the stage of larger and fewer
groups, natural selection among groups necessarily became inefficient.
And as the social relations within these groups resulted in a more ef-
fective extension of aid to individuals and families in need of it, nat-
ural selection within groups also slackened off. Today it is evident
that these two processes are rapidly approaching their limit, that of
a world-wide de facto socialized community where everyone is helped
to live according to his need and to reproduce according to his greed
— his lack of foresight, skill, or scruple.

Thus we cannot extrapolate from the past to the future and say
that culture will inevitably result in biological betterment. On the
contrary, there is now a negative feedback from culture to genetics;
for, as Rensch pointed out in Panel Three, the saving of lives for re-
production by ever more efficient medical and other technical and
sociological aids inevitably results in an increasing accumulation of
randomly occurring detrimental mutations. These must adversely af-
fect health, mtellect, powers of appreciation and expression, and the
genetic basis even of our co-operative disposition itself.

At the same time, the disappearance of subdivision into small groups
removes the basis for evolutionary experiments that result in break-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 215

throughs, as Wright pointed out in Panel Two. In fact, with our co-
operative disposition that forms the biological foundation of the all-
important human system of morals and values, the processes pointed
out by Wright come into play even more strongly. Without subdivi-
sion into small competing groups, there is no effective check on the
higher multiplication rate of those individuals whose genes tend to
result in social parasitism, that is, in self-aggrandizement at the ex-
pense of the group as a whole. Here, beyond the mere passive ac-
cumulation of detrimental mutations, there is a more rapid deteriora-
tion through active selection in a direction antagonistic to the welfare
of the group; and, by a curious inversion, the less fit for the species
as a whole become the more fit in the narrow sense of reproductive
survival.

Any attempt by culture to deal with these difficulties by amehora-
tive measures directed only at the phenotype and lessening for the im-
mediate generation the harm done by the given genetic variations
is ultimately self-defeating because of their greater accumulation.

Kluckhohn: It is a great pleasure to hear a famous geneticist talk
so eloquently about culture and negative feedback from culture to
genetics. But I think I should warn you, sir, that you had better be
careful, or, like our fellow panelist Huxley, you will find yourself
honored with an editorial in the World's Greatest Newspaper.
I One topic that Muller introduced was the role of symbols. In an
exceedingly influential paper some twenty years ago Leslie White
forcefully and clearly wrote about the symbol as the basis of human
behavior.

White: In the Descent of Man Charles Darwin argued that man
is not a unique animal, that his mind differs from those of other ani-
mals merely in degree and not in kind. This question is still open, and
reputable scientists are arrayed on both sides. But I believe there is
enough evidence to close the question once and for all and to estab-
lish the uniqueness of man beyond doubt — which means, of course,
that I place myself among those who believe that man is a unique
animal.

. The trait or characteristic that distinguishes man from all other

I animals is the ability freely and arbitrarily to originate and bestow

meaning upon things in the external world and to grasp and compre-

j hend these meanings. I should like to call this the "ability to symbol,"

and I should like to use the word "symbol" as a verb. I think it would

be much better to say that man has the ability to symbol than to say

i that he symbolizes. Since there is a kind of behavior that consists of

originating and bestowing meaning upon things, why not give it a

name, and why not recognize it as a verb and call it "symbol"?

216 • ISSUES IN EVOLUTION

"Symboling" can be illustrated by articulate speech, or fetishes
or holy water. Holy water, for example, has a meaning that has been '
originated, determined, and bestowed upon it, which cannot be grasped
and comprehended with the senses. Symboling is essentially a process »
of trafficking in meanings that cannot be comprehended with senses >
alone. There is no way to distinguish holy water from ordinary water
with the senses or by any means of physical or chemical analysis. The
same is true of fetishes or of the sounds of which articulate speech is
composed. Of course, articulate speech is the most important and char-
acteristic form or expression of symboling.

At this point it might be well to note that green triangles and redl;
circles used in laboratory experiments with rats are not symbols, al-
though they resemble symbols at some points. The meanings of sym- •
bols are not inherent in their physical forms. These red triangles and I
green circles are not symbols because the rats do not and cannot de- •
termine their significance or endow these physical forms with it. This ;
is done by the experimenter. The rats can learn these meanings, but
they cannot originate and determine and bestow them. This is the •
fundamental difference between the mind of man and that of other
animals, and it is the only thing that does distinguish man in any sig-
nificant manner from other animals.

So far as I have been able to discover, virtually nothing is known i
about the neurological basis and mechanism of symboling. In my paper
for this Centennial, I tried to show that the ability to symbol is the
logical and biological culmination of a process of the evolution of
"minding" that began with the origin of life. I am not going to dis-
cuss the four stages in the evolution of minding at this point. I might,
however, say in closing that the ability to symbol, prunarily in its ex-
pression in articulate speech, is the basis and substance of all human
behavior. It was the means by which culture was brought into exist-
ence and the means of its perpetuation since the origin of man.

Kroeber: White has just mentioned that symbols in language and
culture have a quality of arbitrariness. That may sound as if it dimin-
ished their value. But it is an inherent property of symbols. And it is ^
important because it makes it necessary for symbols to be learned.
They can be acquired only by learning; on account of their very arbi-
trariness, they cannot be congenital and instinctive. This is a conse-
quence of culture's being — as was said in our agenda — exosomatic.

That word exosomatic — "outside the body" — bothers some people;
but there is no doubt that culture is produced and used by man much
as a coral reef is exosomatic in being produced by the bodies of polyps
and then becoming the basis of their environment. Both coral reefs
and culture— I am aware of the contrast, and it is deliberate, but there

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 217

is the common element — are social products of multiple lives of or-
ganisms, developing continuously, without saltation or leaps, and di-
rectly affecting the manner of life of future individuals of the species
— and sometimes indirectly of other species also.

Coral reefs consist of calcium carbonate of a certain structure.
Culture consists of artifacts and mentifacts in reciprocal counterpart.
It is the idea of a machine that is acquired and transmitted by learning,
but it is the machine that runs. Books and such are the objective ex-
pression of subjective knowledge, values, emotions, and idea systems.

Huxley: I was most interested in White's presentation. But I should
maintain that a superorganism looking at the process of evolution on
earth from the outside would say that man's uniqueness definitely lies
in the cumulative transmission of knowledge. This is a new property
of evolving life. It depends on this capacity for symbolization but
is not identical with it.

Although, as Kroeber said, man has to learn these symbols, some-
thing facilitating symbolization must have been put in his germ plasm
by natural selection. Man is genetically a symbolizer, although he
doesn't know what he is going to symbol. He is genetically a believer,
as Waddington pointed out, although what he believes is not prede-
termined. He is genetically a comprehender, although his compre-
hension may go off the rails. But he has a genetic urge and a genetic
capacity to do these things.

Kluckhohn: We need a biologist to lead us gently by the hand
into point 3:

In man, biological evolution through gene shuffling, selec-
tion, and mutation can go on simultaneously with cultural
evolution, and they are both operative. But cultural evolu-
tion has become much the more effective and dominant. The
time seems past when biological evolution, in any single
species other than man or in all of them combined, could
rival or surpass man's cultural evolution. The opposite
seems already to be true.

Anderson?

Anderson: Man is a part of nature. The big evolutionary explo-
sion since the Pleistocene is the plants, the animals, the great unseen
clouds of micro-organisms that live in and around our homes, our
soils, our crops, our very bodies. We are in an evolutionary flowering.
Even our weeds are new — weeds like dandelion, weeds like rats. Even
that deUghtful fly, Drosophila, was a garbage-pail weed until domesti-
cated at Columbia University as a great, evolving, scientific tool.

[Steward: The view that cultural evolution is psychosocial (Hux-

218 • ISSUES IN EVOLUTION

ley), exosomatic (Kroeber), superorganic, or culturological ascribes
different cultural patterns to phenotypical, rather than genotypical,
determinants; everyone agrees that cultural differences do not reflect
genetic racial factors. This is not to say, however, that biological fac-
tors are irrelevant to the nature of culture. We need only imagine a
society of asexual individuals who reproduced parthenogenetically,
with offspring budded as full adults from the head, let us say, as
Athena sprang from Zeus. Such a society would lack families, kin-
ship systems (except unilinear ones), socialization of the young, sexual
reciprocity in function, and age distinctions in role or status.] *

[Hallowell has cogently stressed the importance of viewing human
society with reference to societies among the lower primates. It is
also worth noting that biological factors are particularly obtrusive
in primitive societies, which are characteristically structured along
lines of sex, age, and kinship. While the panel has not yet discussed
whether cultural, like biological, evolution is based on universal prin-
ciples or processes, I suggest that purely culturological principles prob-
ably manifested themselves most clearly after the agricultural revolu-
tion. The simple biological facts of life, of course, are culturally
patterned in many ways in the primitive world; and they are not ab-
sent, although increasingly overlaid by non-biological configurations,
in the modern world.]

Kluckhohn: If I am not mistaken, Polak, you think that cultural
evolution is more like biological evolution than some of us would hold.
Is that right?

Polak: That is quite true. I think that if biological and cultural
evolution are viewed as long-term processes, their over-all mechanisms
seem fairly identical, as do their operational techniques or general
principles for transforming the past and present into the future.

It is my impression that we have been so eager to accentuate the
contrasts that we seem to have ignored this important similarity. Early
post-Darwinian biology and its related sciences were primarily con-
cerned with a reconstruction of the past and were not much inter-
ested in a dimension or continuum of time that included the future.
In the struggle against vitalism and similar theories, the idea of an
evolutionary agency directed toward the future was automatically
condemned as completely unscientific. Modern social and behavioral
sciences, for exactly the same reasons, are averse to using such time
concepts of progress. Most social scientists, afraid of mystical or
philosophical implications, went to the other extreme and excluded
all directional progressive agencies from their subject matter.

* This and other bracketed paragraphs were submitted in writing after the session.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 219

After the victory of mechanistic theories in biology, it again be-
came possible to describe the mechanisms of Darwinian evolution in
terms of time and orientation directed toward the future. Probably
this would have affected the behavioral sciences, had not genetics,
meanwhile, become dominant in biology. Since neither genes nor
chromosomes nor nucleic acids are factors in culture, which involves
mental and social agents, a sharp dividing line between the two kinds
of evolution was maintained by most persons, sometimes to the point
of denying any cultural evolution at all.

I think that cultural evolution as a long-term process is subject to
almost the same guiding or directive agency as that characterizing bi-
ological evolution. It is oriented and preadapted toward the future
and progressive improvement. Its mechanisms select cultural types by
preferring those types that, by their power of qualified anticipation,
have acquired optimal potentiaHties for cultural advancement to a
higher level. By developing from an unconscious and mechanical ad-
vancement to a level of conscious and purposeful end-directedness,
man's cultural evolution widely overstepped the boundaries of bio-
logical evolution.

Huxley: I agree with Polak about the similarity — not the identity
— of many trends in the course of psychosocial evolution and bio-
logical evolution. But it seems to me a complete confusion of terms
to call the mechanisms similar. The mechanism of biological evolu-
tion is the natural selection of genetic variants. From what has al-
ready been said here — and from all our knowledge of social anthro-
pology and history — this is not what is primarily operative in cultural
evolution. Biological evolution was not deliberate. It was teleonomic,
in that the blind mechanism of natural selection forced or guided it
along certain directions; but it was not deliberate or purposeful, as
cultural evolution is in part.

[Stew^ard: Huxley's view of cultural evolution as partly "deliberate"
might give the comforting thought that we may in some measure con-
trol our destinies. A naturalistic understanding of cultural evolution,
however, must assume that goals, no less than other aspects of culture,
have determinable causes. In early human evolution, man, like other
animals, strove for sheer physical survival. Much later, this essentially
biological goal was supplemented by objectives relating to new kinds
of production, social statuses, ethical systems, and religions. It is not
enough to say that man chooses goals deliberately and with aware-
ness. As students of cultural evolution, it is our job to find out why,
in each cultural tradition and development stage, man chooses some
goals and not others.]

220 ■ ISSUES IN EVOLUTION

Kluckhohn: Huxley, would you go on to point 4?

As far as we know now, cultural evolution in Homo sapiens
is essentially independent of gene differences between hu-
man subgroups or races. In that respect, the courses of
organic and of cultural evolution are different.

Huxley: Muller pointed out that in the very early stages of differ-
entiation of hominids and hominines, natural selection among small
groups led to genetic differences between the groups. After Homo
sapiens became the dominant type and spread over the world, he dif-
ferentiated into what have been called the major races of mankind
(in animals one would call them "subspecies") with certain adaptive
differences in structure. But this process never reached the stage of
full speciation. Later, man's restlessness and cultural habits brought
about convergence again, so that mankind is now a single interbreed-
ing group without sharp subdivisions. It is extremely difficult to meas-
ure "racial" or ethnic differences because cultures and genetic back-
grounds interact; but, as far as we know, cultural evolution in Homo
sapiens is essentially independent of genetic differences between hu-
man subgroups or races. Significant genetic differences between races
are very sHght, and there is an enormous amount of overlap. The main
differences resulting from cultural evolution are independent of these
genetic differences.

Kluckhohn: Virtually all anthropologists would be in complete
agreement with Huxley.

We are now going to consider points 5 and 6 jointly:

5. While involving redculate aspects, especially among the
lower taxa, biological evolution generally takes the form
of a branching tree made up of diverging lines of descent.
The lines of cultural descent may run parallel, or they may
diverge through innovation, isolation, adaptation to a
local environment, etc., but at the same time they con-
verge and commingle through contact, spread, diffusion,
communication. Cultural evolution is different from bio-
logical evolution, in that aspects of culture — ideas, tech-
niques, institutions — can be almost indefinitely combined
and hybridized, regardless of the dissimilarities between the
cultures that produced them.

6. Cultural accumulation occurs in economy, technology,
and science. Small-unit social groupings such as the family
tend to persist, while larger pohtical integrations tend to be

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 221

superadded and to dominate. In other fields, especially the
stylistic aspects of culture, successful creative efforts come
mostly in non-cumulative intermittent bursts or pulses.

Number 5, you will note, begins with a characteristic academese
phrase: "While involving reticulate aspects. . . ." These are rather
dark words, and we shall have to ask Anderson to tell us what they
really mean.

Anderson: Just one fundamental philosophical point. Phylogenies
are constructed by the mind. Therefore, when we compare plant phy-
logeny with cultural phylogeny, we are not skating on the useful, but
dangerous, thin ice of analogy. There are two basic patterns for all
phylogenies: relationships branching like a tree — dendritic — and those
like a net — reticulate. We are learning to think in terms of a combina-
tion of both patterns. We know that there are many intermediates
between the netlike tree and the treelike net. It takes the sharpest
minds, with the best data, to visualize the right model and to shift
models.

Kluckhohn: It is time to take up those phases of cultural evolu-
tion that the archeologists know most about. Adams, I don't know
whether you are more reticulate or more dendritic, but give us some
facts anyway, will you?

Adams: I might describe myself as more substantive and less pro-
grammatic.

Huxley: Are you dendritic?

Adams: I shall delay answering that question until we have gone
a little further.

It seems to me that one of the main functions of this panel is to
deal with the questions of progress and accumulation in culture and
to contrast these with the biological record. That cultural accumula-
tion appears to occur more rapidly in economy, technology, and sci-
ence seems self-evident; yet it is fruitful to analyze and qualify this
seemingly self-evident assertion.

One who approaches this question from the kind of data to which
the historian or the archeologist is accustomed should be aware at
the outset that he cannot escape from certain built-in distortions.
Archeology must be concerned primarily with material data, with
imperishable remains. From this concern come preoccupation with
this kind of information and a tendency to see in imperishable remains
and the institutions directly connected with them a fundamental, causa-
tive role that in broader perspective one might wish to question.

A good example of this distortion is the importance sometimes at-
tached to the introduction of metallurgy at the beginning of urban

222 • ISSUES IN EVOLUTION

life. A revolutionary role is frequently claimed for the very small
number of craftsmen who began to produce metal weapons, cult ob-
jects, and the like. I do not question that they were a new feature or
that their role was important. But I think that some archeologists,
such as V. Gordon Childe, have unduly stressed technology as an in-
dependent causative agent, at the expense of the social institutions
in which it was imbedded and which gave it influence and meaning.

Another important kind of built-in distortion affects the student
of ancient history as well as the archeologist. Whether drawn from
texts or excavations, our information comes from cities, temples, and
palaces, from the kinds of centralized units on which archeologists
naturally concentrate to fill museums and make use of the descriptive
detail the texts contain. But these centralized institutions, supported
by the small margin of surplus obtained from the countryside, as a re-
sult of outside pressures were almost certainly more prone to fluctuate
than was the underlying agricultural economy. Hence this preoccupa-
tion with dynasties, wars, and institutionalized religions — the old his-
toriographic foci — tends to establish the cyclical aspects of history
as more important than they really were. Therefore, it may lead us
to overlook accumulation where, in fact, it really did occur. I do not
deny all cyclicity, of course, for nomadic resurgences into formerly
urban areas are fairly common. But I insist that these must be seen
in a perspective that is not gained only from centers that were most
subject to disruption.

In a broader sense I am very skeptical about the contrast of a rate
of accumulation in technology and science with another rate in values
or political institutions. All these changes occur in the matrix of hu-
man society, and I don't think they can be understood outside that
matrix. The most important aspects of accumulation, to me at least,
are those having to do with the size, complexity, and adaptive effi-
ciency in some general way of the social unit; and all the differing
aspects of accumulation that have been mentioned are linked in vari-
ous ways to these much more basic features.

Consider technological changes again. Going back to the period
of the urban revolution, which I know best, one sees the associated
technological improvements as being primarily of an organizational
character: increasing state capitalization, emphasis on weapons, ra-
tionalization of the procurement of raw materials, increasing size of
production unit, etc. The transformation of a technology is most use-
fully understood, not as a series of inventions, but as" the organiza-
tion of new inventions and old techniques within a social framework.

Similarly, if we take features of rehgion, how are we to see ac-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 223

cumulation in the succession of gods and the changing emphases on
gods in the ancient Near East? Only by relating these to the expand-
ing empires that are appearing at the same time, to the enlarged so-
cial unit, and to the greater consciousness of a wide oikumene ex-
tending beyond any poHtical boundaries.

Having dwelt somewhat too long on the background of the issue,
I would very briefly suggest that, in fact, accumulation is evident, al-
though I would not now put this in the terms used in point 6 of the
agenda. One sees accumulation perhaps most strikingly in the increas-
ing complexity of a stratified society — in the emergence of an increas-
ing differentiation in wealth and power as one moves up the scale from
village to town to city-state to empire. A second major trend of the
same order of importance is urbanization, which is linked with the
appearance of militarism and with the formation of larger and larger
territorial units. The expansion and increasing capitalization of agri-
culture is a third trend that I think is beginning to be traced. The
development of a greater degree of specialization of labor might be
another such trend.

Finally, and less surely, there may have been a trend toward sec-
ularization, which, if it is a trend at all, is certainly far more tenuous
and subjectively distinguished. Perhaps it proceeds less steadily and,
as it were, in disjunctive jumps. At any rate, there is a long span be-
tween the man-centered universe of Thucydides and that of Machia-
velli, with nothing very similar to either of them. Or, again, there is
a sharp decline in this same sense from Elizabethan England into the
rather dogmatic Puritanism that followed. But from a sufficiently long-
range point of view, I think one might still wish to distinguish this
as a trend similar to the others.

Willey: In general, I would agree with Adams, but I should rather
put it this way: Technological innovations are subject to selective
pressures similar to those in biological evolution — subsistence pres-
sures related to the natural environment and, in general, to coping
with nature. In such selectivity it is easy to see a fairly obvious adap-
tive direction. Selective pressures affecting innovation in style, on
the other hand, are weighted by cultural and social environment, and,
as Adams indicated, an adaptive direction is not easily seen.

Huxley: I entirely agree that almost everything accumulates, but
I don't see how it can be denied that some things accumulate faster
than others. Also, in a propitious environment — and that is what
Adams stressed — new inventions may have a decisive effect on the
social structure or the social system. It is a feedback system.

Adams: One has to attach a causative role to the introduction of

224 • ISSUES IN EVOLUTION

certain inventions, for instance; but frequently these inventions are
regarded as capricious elements, essentially external to the society,
and their cultural context is not described or understood.

Kluckhohn: We shall now move on to points 7 and 8, taken to-
gether:

7. On account of their constant interflow, cultural phe-
nomena allow cross-cutting classification into equally valid
(1) historical units of cultures ("civilizations") or (2) ab-
stracted "levels of integration" (Steward). The civilizations
correspond imperfectly to biological clades or taxa; both
represent sequences of historic continuity, and both show
potentialities for survival value and further advancement.
Sociocultural levels or stages correspond roughly to the bio-
logical "grades" attained by innovating anagenetic im-
provement and maintained by stasigenetic persistence.

8. Organic evolution is always continuous, as are cultural
evolution and human history. But it is punctuated by rela-
tively brief periods of crucial change, in which previously
non-dominant forms of life achieve an evolutionary break-
through to a new level or grade of organization and ca-
pacities. This new grade then undergoes rapid and intensive
adaptive radiation and attains dominance, maintained there-
after with lessened change. Examples are the taking-over of
dominance from Triassic-Cretaceous reptiles by warm-
blooded mammals and birds at the beginning of the Ter-
tiary and also the breakthrough of cultural evolution with
man in the Pleistocene.

Kroeber: I should like to begin with a point that my neighbor and
partner Huxley took over from Rensch and enlarged and with which
Simpson coincided. They make the point that biological evolution has
three major aspects or modes: one that leads to divergence, another
to persistence, and the third to improvement. My point is that, al-
though the mechanism of culture is quite different, these three modes
can also be distinguished in the evolution of culture.

For correctness of the record, I use the technical terms that these
three modes of evolution bear. Cladogenesis, leading to genetic diver-
gence and the enrichment of total life in multiple phyla or grand di-
visions, corresponds in culture to the development of the greater civi-
lizations, separate in space or tune or both, but each with a continuous
history — well, I really don't know which it is as between ontogeny or
phylogeny. View an entire civilization as an end result, and its de-
velopment is an ontogeny. But, insofar as each major civilization has
many components or strands and has gone on for many generations
of men, its growth or history is also a phylogeny.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 225

The second major aspect of evolution is stasigenesis, which is con-
cerned primarily with persistences; and this is exemplified by the minor
and belated cultures of primitive populations and partly of peasants.

Third, biological anagenesis or improvement works by break-
throughs to new grades or dominant levels of life; these correspond
to what in culture have been recognized and called by White, "stages,"
or by Steward, "levels of integration," or by the late V. Gordon Childe
and by Adams here just now, "revolutions" — as, for instance, the
urban revolution, the food-producing revolution as compared with
the earlier food-gathering stage, or our contemporary culture seen as
an industrial revolution.

In short, all three modes or aspects of evolution are as recognizable
in culture as in biology, and all three must ultimately be studied in
their interrelations if we are to have a picture of total human evolu-
tion.

Huxley: Cladogenesis, of course, is Anderson's "tree," the dendritic
or branching pattern. It is not confined to the major units, but goes
on within the subgroups also, doesn't it? It is perfectly true that in
culture you can't distinguish ontogeny from phylogeny: you can't
separate them as you can in a higher organism, just as you can't sepa-
rate germ plasm from soma in a culture. The two are one. As for
stabilization or stasigenesis — the tendency leading to persistence —
there is always selection for stable forms, which, if successful, tend
to persist. We shall discuss improvement later, when we talk about
long-term trends.

Finally, I would say that cultural evolution includes a fourth process
or mode of evolution, which is diffusion. Gene diffusion and conver-
gence have played some part in evolution above the species in plants
but have been of very little importance in animals. In man, both gene
diffusion and convergence have played an enormous part. They have
fused all the human races into one. And directly that happened, there
was convergence of cultures, too, through culture contact and what
Kroeber calls "idea diffusion." So you have a new process superposed
on the other three.

Kluckhohn: We shall now move on to points 9 and 10:

9. Within human cultural evolution several corresponding
major critical breakthroughs (sometimes called "revolu-
tions" in prehistory and history) have been discerned in the
accumulating empirical evidence. These are (1) food
production, beginning gradually about 7000 B.C.; (2) a
syndrome centering around 3000 B.C. in which writing,
metallurgy, urbanization, and political structures were first
evolved; (3) from about 600 B.C., religions organized both

226 • ISSVES IN EVOLUTION

doctrinally and institutionally; (4) beginning about a.d.
1600, a level or grade of civilization characterized by the
rapid and progressive development of science, technology,
invention, industry, and wealth.

10. In the light of present evidence, these respective ad-
vances concerned primarily subsistence in stage 1, general
civilization in 2, religion in 3, and secular activities in 4,
with definite, perhaps reactive, change of emphasis or direc-
tion in each surge as compared with the preceding one. A
world-wide spread (roughly corresponding to "adaptive
radiation") in the fourth stage is apparently still taking
place. When it shall have covered our planet, a degree of
temporary stabilization may occur.

You will note under point 9 a series of four so-called "revolutions."
First is food production. When I think of food production, I think
of Anderson.

Anderson: As a demonstration of its use or as an authority?

Kluckhohn: Both.

Anderson: Let us first ask What did not happen? Agriculture did
not begin in Europe. We are looking at the problem with European
eyes; our minds are using European words. When we observe and
reflect on the patterns of agriculture we find in Africa, Latin America,
and Asia, we see that the earliest agriculture in the Near East is very,
very late.

Kluckhohn: Willey, are you on time?

Willey: These revolutions outhned in the agenda, or at least the
first two, occurred in the New World also, but the dates shown apply
only to the Old World. In timing and sequence there are some very
interesting contrasts, as well as sunilarities, between the two hemi-
spheres.

Food production, beginning about 7000 B.C. in the Old World,
means a threshold of village agriculture and a village community sus-
tained by plant cultivation. In the New World, some plants were cul-
tivated in northern Mexico at least as early as the interval between
7000 B.C. and 5000 b.c, but in a context of very simple seed-gather-
ing cultures. (If there are earlier evidences of plants in the New World,
we certainly don't have them archeologically. Perhaps Anderson will
refer to this again. )

In the New World, it took from around 7000 b.c to about 1500
B.C. to reach a level of estabUshed village agriculture. I don't know
whether such a long period of incipient cultivation occurred in the
Old World before 7000 b.c, and I should be interested to hear Adams'

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 227

views. I should think that glaciation might complicate pushing it back
beyond 7000 B.C.

In the Old World, an interval of about four thousand years sepa-
rated the threshold of village agriculture and the attainment of the
city syndrome, with writing, metallurgy, urbanism, and political struc-
tures. In the New World, this city syndrome — or a pretty good repHca
— appeared in Middle America and Peru as early as the beginning
of the Christian Era. Not all these city traits are always found in the
same context. Writing, for instance, developed in the lowlands of
Middle America as early as the beginning of the Christian Era, but
it was not associated with metallurgy and probably not with urbanism.
In the Valley of Mexico, urban life and the development of a state
organization must be associated with the Teotihuacan civiHzation,
dating back to a.d. 1 ; but neither writing nor metallurgy was present.
In coastal Peru, metallurgy and urbanism are found, but not writing.
Whether these various city-type traits in the New World would even-
tually have coalesced into a single culture or civilization, we don't
know; this had not happened at the time of the Spanish conquest by
A.D. 1500.

There is only a fifteen-hundred-year gap between village agricul-
ture and cities in the New World, and a four-thousand-year gap be-
tween these events in the Old World. I should like to hear Adams say
something about this.

Adams: We have been burned so often in recent years by changing
radiocarbon dates that I am no longer sure what chronologies I do
believe. There certainly seems to be this contrast, but I have no ex-
planation for it. Until more is known about how it developed, I would
rather just leave it as one of those unanswered questions that plague
us.

Anderson: I should like to interrupt, if I may. Many of you know
that I am a heretic on this question. I did not say that agriculture came
from Asia; I said we must start thinking about it.

Adams: The available archeological evidence bearing on the ques-
tion that Anderson is asking is that in the Near East before 7000 B.C.
we find nothing certainly cultivated except wheat and barely. We are
told that some specimens of wheat and barley from Jarmo are very
close to their wild state. Perhaps there are questions as to what the
wild state was.

Anderson: I agree completely. Those facts are all absolutely
straight insofar as they have been reported.

Kluckhohn: You are both happy then.

You will note that the third revolution listed in point 9 deals with

228 • ISSUES IN EVOLUTION

what, throughout most of recorded history, most people thought of
when they thought of development or progress. Now, Kroeber, skepti-
cism has always been the chastity of your intellect; but would you
mind talking about religion?

Kroeber: I reahze that item 3 has about four spaces less than one
line in the agenda: perhaps it does need a little factual elucidation.

The third stage, or revolution, there mentioned is primarily religious
in character or, perhaps better, religio-philosophical. It occurred in
the Old World, nearly all of it in Asia, within the six or so centuries
before Christ and the six or so after.

This 1 200-year phase includes both Confucianism and Taoism and
the whole classic Chinese philosophy. In India it comprises Buddhism,
the rival Jain religion, the Sankhya philosophy, perhaps the Vedanta
culmination under Sankara about 800 a.d.; in Persia, Zoroaster and
the Avesta; in Palestine, the non-legendary historic prophets of Juda-
ism. It would comprise Greek philosophy, culminating in Plato, Aris-
totle, and the Stoic school. It would include Jesus, Paul, and Christian-
ity as far as Augustine. It would also include the minor rehgions of
the Near East: Mithraism, Manichaeism, Gnosticism, and most of
Talmudism, and, finally, Mohammed and Islam.

These rehgions are characterized by several features:

First, systematization — a formulated doctrine or dogma.

Second, exclusiveness, incompatibility with other faiths, along with
tendencies toward intolerance and propaganda.

Third, institutionalization — becoming social organized bodies as
well as faiths.

Finally, most are monotheistic, a few dualistic or atheistic.

These common features, plus the circumscribed area and the limited
span of origin, carry some suggestion that all or most of these religious
developments may form part of one breakthrough to a new grade of
cultural evolution.

Adams: One can identify a syndrome of related social, cultural,
technological, and economic changes around the food-producing rev-
olution, around the industrial revolution, and around the urban revolu-
tion. In time we may very well find that Kroeber's third level, char-
acterized by new features of rehgion, is also part of a syndrome of
change. In the Near East I think we are beginning to identify a very
substantial change in the subsistence base that comes in just at this
time — a much more massive artificial approach to canal irrigation
and so on. I am merely suggesting that we recognize that, while in
the light of present knowledge this third level is identified as a pri-
marily religious change, it may very well be a much broader syndrome.

Kluckhohn: White, you have always been interested in the sci-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 229

entific energy and similar aspects of evolution. I wonder if you would
talk a bit about the fourth revolution.

White: The concept of revolution as it is applied to culture change
is useful, but I think it should not be tossed around loosely or in-
discriminately. We should distinguish major revolutions from the
minor revolutions that are merely aspects of a larger revolutionary
change in culture. As yet we lack an adequate taxonomy of revolu-
tions in the course of culture history. I like to regard revolution in
culture from the standpoint of the thermodynamic nature of socio-
cultural systems. A sociocultural system is a thermodynamic system
whose main function is to harness energy and put it to work in the
service of the human beings embraced by that sociocultural system.

From this point of view there have been only two major cultural
revolutions in human history, and the second one has not yet run
its course. The first of these two great revolutions that profoundly
changed culture from top to bottom has often been called the "agri-
cultural revolution." It consisted of harnessing solar energy in the
form of domesticated animals and cultivated plants. The second great
cultural revolution in human history was what I would call the "fuel
revolution," or perhaps the "power revolution," which began in the
eighteenth century with the harnessing of solar energy in the form
of coal and petroleum; and, of course, more recently new sources
of energy have been harnessed and are being put to work for peace-
ful purposes as well as for military use.

Compared with these two great, profound, and comprehensive cul-
tural revolutions, all others pale into insignificance. I think that
V. Gordon Childe includes too many revolutions in his account of
human history. His urban revolution, for example, seems to me merely
the culmination of the agricultural revolution.

These great revolutions begin as technological revolutions and are
followed by social, and then by ideological, revolutions. The second
great cultural revolution of modern times began, of course, as a tech-
nological revolution that has not yet run its course; and we are at the
present time in the midst of a profound world-wide political, social,
and economic revolution.

Anderson: May I interrupt again? I like White's point very much.
I wish you archeologists — it's your field — would remember it when
you start thinking about the domestication of plants; to read your
papers, one would think that man had never been anything but hungry.
Wasn't he ever scared? Wasn't he ever awed? Didn't he think a flower
was beautiful?

Kluckhohn: Kroeber, did you ever think a flower was beautiful?

Kroeber: I wasn't asked that. Speaking to Adams' point, I am sure

230 ■ ISSUES IN EVOLUTION

there were such additional innovations. For instance, among the non-
religious features of this religious syndrome were the invention of
coined money and the first fully developed democracies.

[Steward: I should like to raise this question: Do these four major
breakthroughs, each of which is delineated as distinctive in character,
imply successive changes in the very principles of cultural evolution?
My question betrays my interest in cultural causality. While Kroeber
has often gently reminded me that one does not have to be interested
in causes — a contention I cannot dispute — it is difficult to see how
causes, processes, or principles can be ignored in a discussion of cul-
tural evolution.]

[In order to probe the possibility that there is a continuity of evolu-
tionary principles throughout culture history — principles as invariant
as natural selection and heredity in biological evolution — I suggest
that we tentatively combine Adams' idea of a syndrome of factors with
White's concept of culmination to explain all four breakthroughs. The
food revolution permitted internal social-role specialization and led
to new inventions, while population growth and centralization of ad-
ministration and other functions eventually culminated in urbanization
and state formation. The spread of the key features of this syndrome
by about 1000 B.C. to areas beyond the rather absolutistic states of the
great river valleys may well have become preconditions of new social
arrangements that underlay the emergence of a series of new rehgions
beginning about 600 B.C. The fourth breakthrough, as White has fre-
quently stressed, is partly a repetition of the first, in that new sources of
power and use of machines went hand-in-hand with intellectual de-
velopment and new technologies and initiated further social trans-
formations.]

Huxley: It is extremely important to recognize another similarity
between biological and cultural evolution. In both, one finds break-
throughs from one stabilized grade of organization to another, al- l
though they are rare and appear difficult to make; and if the new type
of organization is successful, it will increase and spread, will become
stabilized in its turn, and will persist for a long time.

I know that I am an outsider in anthropology; but I have tried to
look at the history of man with the eye of an evolutionary biologist.
And it seems to me that each psychosocial grade always involves two i
distinct aspects: the material and institutional aspect and the psycho-
logical or symbolizing or ideological aspect, with ritual and religion,
myth and science. Although material technological progress is ob-
viously the basis for material advance, as Childe and others have
stressed, yet to leave out the other aspect is not scientific, because there
is always an interplay or feedback between them. The preagricultural

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 231

Stage had its own rituals and magic. With the agricultural stage came
a totally new type of magic ritual concerned with death and resurrec-
tion, based on the seed and its rebirth. The urban grade was based on
primitive technology and organized irrigation, but it also soon led
to the organization of religious ideas and to the beginning of science
and mathematics. Later you have the scientific grade, with its industrial
basis and its urge to explore, but still based on the idea of creation and
on an essentially static theology. And today I would say that, thanks
to Darwin, we are just on the threshold of the evolutionary grade.
This is naturalistic. It has rejected the supernatural idea of creation
for that of material progress; and it is trying to think in psychological,
as well as in economic and technological, terms. I think my anthro-
pological friends will agree with me that in each grade the material
and psychological components interact and that both are essential.

Kluckhohn: What do you mean, your anthropological friends?
You are a visiting professor of anthropology here at the University of
Chicago, and you have spoken exactly like one. Now would you be
so kind as to take us into the eleventh and twelfth points?

1 1 . While adaptation on the part of the organism has been
strongly stressed as a primary factor and result in the evolu-
tion of animals and plants, both by Darwin and by modern
evolutionists, it has been a much smaller consideration in the
exosomatic physical and organic environment through
selection. The function of culture is not only to adapt man
to his environment, but also to adapt man's environment
to himself by suitably modifying it.

12. The basic and primal inventions of culture — fire,
clothing, shelter and constructions, tools and weapons, food
preparation, cooking and cooking utensils, storage of sur-
plus food and later food production by farming and herd-
ing — all these modify, change, or abolish difficulties existing
in the natural environment by (partly) substituting an arti-
ficial (man-made) environment of artifacts. This indis-
pensable material basis of human culture is subsumed under
the term "technology" and remains the chief means of sub-
jugating environment as well as adapting to it.

Huxley: Animals, of course, grow their own tools. The wing of a
bird or the tongue of a woodpecker is an incredible implement for its
special function. Among animals, one also finds many so-called exo-
somatic organs: spiders' webs, birds' nests, etc. But these are all ge-
netically determined. Yesterday's panel cited a few cases of the actual
use by animals of tools in the strict sense — although never the fashion-
ing of them. But here again, the use of such tools as the twig employed

232 • ISSUES IN EVOLUTION

by Darwin's finch to act like the tongue of a woodpecker seems ge-
netically determined. The big changeover in man was that he started
making tools for a purpose and then purposefully improving them.

Adams: I think Anderson's earlier complaint about the unfortunate
way we have focused ourselves fairly exclusively on adaptation, in the
narrow sense of meeting immediate subsistence needs, applies better
here than it did earUer; it applies at many points throughout.

Within human societies the notion of survival of the fittest is largely
shaped by cultural factors, as has been said. Man does not face his
environment alone, as the wording of point 12 seems to imply, but as
a functionally specialized member of a group — and, as time goes on,
of an increasingly complex group that is exploiting an increasing num-
ber of ecological niches under increasingly artificial conditions, created
by societies themselves. Here one needs only to mention such processes
as deforestation, the creation of grasslands as a result of certain kinds
of agricultural and other uses, and the appearance of salinity in large
agricultural areas.

It seems to me more important to stress this social aspect of sur-
vival than the technological aspect. In fact, rather than say that "tech-
nology is the chief means of subjugating environment and adapting
to it," we should say that it is the chief immediate means and recog-
nize that technology is brought into play by social organization.

Kluckhohn: One member of our panel very understandably feels
that we have gone on for quite a while in our agenda and in our dis-
cussion without saying much, if anything, about ideas. We have said
something about ideas, but we have not stressed them. We tave talked
about things and food and so on, and even the botanist was rebuking
us for not buying hyacinths. So I am going to ask Polak to redress
the balance a bit.

Polak: I think that the very important role of technology as a
means of transformation has been somewhat overemphasized. Of
course, we are greatly impressed by the agricultural and industrial i
revolutions, but we should not underestimate the creative rnipact and i
molding force of the human mind and man's non-technological crea-
tions. Those creations include religious, ethical, philosophical, and
humanist ideas as well as art. They have been expressed in value sys-
tems and ideologies. Some of these have had a profound influence and
played an important role in adaptation to, and of, the environment.

Though our age values technological invention and material goods
and rejoices for every point at which the standard of living is raised,
this has not always been so. For example, in older China and in the
Hellenistic cultures, the spirit of the times was against technological
innovation. About two thousand years ago the technologists of Alexan-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION ■ 233

dria in most fields knew as much as, or even more than, their counter-
parts of sixteenth- or seventeenth-century Europe — a time lag result-
ing mainly from a different hierarchy of values, a different mental out-
look toward the goals to be reached by man.

In exactly the same way, ideaHsm was an active driving force in
America's rise to world power and cultural expansion. One of these
motive forces was, I think, the exciting idea, later to be called the
"American Dream," of founding a new world of peace, brotherhood,
and happiness, a Utopian quest for group society and the full life and
human dignity. I like to think that such philosophy as is included in
your Declaration of Independence and in your Constitution has had
and I hope still has great potential and constructive power to shape
the evolution of your culture and to change the world.

[Steward: Much of this discussion has turned upon the role of ideas
and ideals in cultural evolution. I should like to know how and why
specific ideas and ideals evolved in relation to technological improve-
ment, population increase, class and state development, and social
transformations.]

Kluckhohn: I think we should move now to point 13 :

13. The result of points 11 and 12 is that most anthro-
pologists and students of culture have been less concerned
with adaptation and its relentless flow than have biologists.
They deal with change, advance, accumulation, and inter-
personal and intersocietal processes, which they have often
assumed to be non-adaptive. Their concerns are usually
microdynamic. Even the term "evolution" tends to be
avoided, partly through persisting reaction against the
speculative pseudo-evolutionistic excesses of anthropolo-
gists in the immediate post-1859 period. As to the macro-
dynamics of cultural evolution, its causes and principles,
and its interrelations with biological evolution, there is as
yet no general agreement. For the near future this sub-
ject needs careful research. This is necessary as a basis for
any attempt to predict or control the direction of cultural
evolution.

That seems to me your baby, White. For years you have poured
acid on some members of our trade union because they practiced cere-
monial avoidance on this great concept of evolution.

White: This subject is one that interests me very much, and I wish
to say something that I think needs to be said, even though it may not
be very pleasant or complimentary to certain people.

I see here the phrase, "Even the term evolution tends to be avoided."
That is a pretty mild statement for what has taken place in the United

234 ' ISSUES IN EVOLUTION

States in the last thirty or forty years. When I was a graduate student,
the chmate of anthropological opinion was definitely and vigorously
antievolutionist. One of our distinguished American anthropologists
said: "The theory of cultural evolution is, to my mind, the most inane,
pernicious, and sterile theory in the whole realm of science." About
thirty years ago I took up the cudgels in defense of cultural evolution-
ism and tried to rehabilitate the theory. I was virtually alone. Many
very uncomplimentary things were said about me for quite a long
time. Finally, these were modified somewhat, and I was called a "neo-
evolutionist," a term which I and Father Wilhelm Schmidt strongly
and vigorously repudiate.

Nowadays, thanks rather largely to the Darwin Centennial Cele-
bration, the theory of cultural evolution is becoming respectable and
therefore popular. And I find that most of my fellow anthropologists
are evolutionists. They are coming from here and there, saying "Why,
I have been an evolutionist all along." I also find that some things
that have been called "history" all along are now appearing in the
clothing and phraseology of cultural evolutionism. It is really ironical
to recall that some thirty years ago one of the arguments used against
the theory of cultural evolution was derived from Darwinism. It was
argued that the theory of evolution was valid and useful in biology
and that it was therefore transferred to the realm of culture, where
it was invalid. Now, a generation or so later, a full turn of the wheel,
Darwinism is putting cultural evolution on its feet again.

Well, of course I am very glad to see this. I only hope that I won't
be excommunicated when the theory of cultural evolution becomes a
full-fledged movement in anthropology, as it seems likely to become.
However, I am not overly encouraged by the swelling of the ranks of
cultural evolutionists at this time, because it takes more than popu-
larity to make a scientific concept sound. And I don't think cuUural
evolutionists are going to be made overnight by the popularity of tele-
vision and other public ceremonies and exhibitions. I think it will take
a great deal more than that.

I wanted to get that off my chest.

Kluckhohn: You certainly did.

Polak: I should like to draw attention to the triumph and tragedy
of cultural macrodynamics. At one time, mostly in Europe, this field
was highly fashionable, but now its accompfishments are not consid-
ered to have been very successful. Social and behavioral scientists have
become wary of all-embracing systems. At present, scientific interest
in the time-dimension process as seen in the rise and fall of civiliza-
tions seems almost extinct or deeply hidden.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 235

Kluckhohn: Excuse me; just one minute. What is cultural macro-
dynamics? Is it the rise and fall of civilizations, or just what is it?

Polak: Yes, the long-term process of the recurrence and the rise
and fall of civilizations.

Kluckhohn: Okay.

Polak: Perhaps we became discouraged and disillusioned too soon.
Here is one of the most important unfinished tasks of social and cul-
tural science. Let me give you one concrete example: A correlation
may be drawn between man's imaginative concept of an ideal future
and his evolutionary course into the real future. More specifically,
such positive, constructive images of the future as the American
Dream can be correlated with a rising civilization, and loss of faith in
coming destiny, expressed in negative images of the future, with a
corresponding decay or disintegration of a civilization. In that case,
just as in biological evolution, the essence of cultural evolution would
be found in its potentialities for preadaptive improvement: potentiali-
ties that may lead to cultural breakthroughs and future progress may
be demonstrable and in part measurable.

This point of view has far-reaching implications. Further analysis
along these lines might make the direction of future evolution at least
partly predictable, and it would also make it more controllable — which
means to adapt the future as far as possible to our ideal ends. It better
explains the significance of the so-called revolution of expectations —
a radical change in the image of the future.

Kluckhohn: In point 14 the key word is "culture history."

The nearest counterpart in anthropology and the social
sciences to genetic evolutionary science appears to be car-
ried on mainly under the name of "culture history" (in-
cluding prehistory) and is naturalistic, empirical, holistic,
seeking continuities and connections rather than phe-
nomenal identities or "regularities" and yet ready to accept
such "regularities" and punctuating cultural "revolutions"
insofar as these are demonstrable. Such knowledge is im-
portant for gaining a timely and adequate insight into the
processes forming the future.

Kroeber: I have always felt that I was doing culture history. Now
it turns out that all this time Leslie White and I have been sleeping
in the same bed for thirty years without knowing it. (No, I am not
the author of the quotation about cultural evolution that he cited. )

I believe that culture history — I am now emphasizing what it says
in the agenda — including prehistory, of course, must be wholly nat-
uralistic and empirical in method. It should be holistic in its ultimate

236 • ISSUES IN EVOLUTION

aim. It should assume continuity as a principle and seek connections
as far as they are demonstrable.

There is another point, however, which is not in the agenda, and I
think it has a certain importance. This is that culture, even in its sim-
ple, merely descriptive presentation, is already a series of regularities.
We are Hkely to forget that fact. Culture is a series of regularities
underlying the multitudinous and varying events of human behavior
in what is ordinarily called "history."

Historiographers as such do not deal with culture: they take it for
granted. They do not bother to tell what the culture is whose events
they are presenting, and so they do not describe regularities. They
concentrate on events. Such is the customary field of the professional
historiographer. But a patterned culture is always impHcit in it.

What the anthropologist tries to do is to make explicit, to spread out
in open view on the table, the cultural patterning that underlies the
stirring events that the historiographer narrates.

Willey: It strikes me that the method of cultural evolution is one
of examining process and, from cross-cultural comparisons, distilling
configurations through time. This I would consider cultural evolution
as opposed to culture history. Does White agree?

White: Thorstein Veblen has frequently been quoted as saying
that there are no synonyms in the English language, and I subscribe
to this opinion. I do not think that "history" and "evolution" are
synonyms. I believe that they represent and express fundamentally
different concepts. In trying to analyze and interpret the phenomena of
the external world, we can distinguish a temporal particularizing
process, on the one hand, and a temporal generalizing process, on the
other. I should like to call the temporal particularizing process, in
which events are considered significant in terms of their uniqueness
and particularity, "history" and call the temporal generalizing process,
which deals with phenomena as classes rather than as particular events,
"evolution." History and evolution are alike in being temporal, dealing
with temporal processes. They are fundamentally different, in that the
one is particularizing, the other generalizing.

Kroeber: I have only just discovered that White and I have been
sleeping in the same bed for thirty years, and now he says that they
were two beds.

Willey: Let me ask this: Is the statement that, in the Middle Ameri-
can area of the New World, a period of food production by plant
cultivation succeeded a period of food gathering a statement of cul-
ture history or cultural evolution?

White: It can be placed in either context, depending on whether
you wish to particularize or generalize.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 237

Huxley: You shift from one bed to the other.
Kluckhohn: Watch these metaphors, gemlemen.
Willey: One more question. Does the size of a geographical area
have anything to do with this?
White: No.

Willey: I think some of our colleagues feel that it has.
White: I wouldn't doubt that.

Kluckhohn: Well, shall we move on to point 15?

The very historization of understanding in science which
our present fourth critical stage of innovation has brought
with it involves greater awareness of evolution and of the
future as well as the past. This awareness will no doubt
produce efforts to direct the course of evolution. No pre-
cedent exists for predicting what success such efforts may
have.

Whether the next grade be attained automatically or
partly by willed planning, the orientation and kind of its
innovations constitute a most significant problem. The ad-
vances of modern science and technology in gaining deeper
understanding of physical, biological, and cultural phe-
nomena and in devising means of controlling them place
in man's hands tools of unprecedented power. The use of
these with insufficient foresight could have undesirable and
even disastrous biological and cultural consequences. Con-
versely, their use with foresight would offer possibilities of
human evolution both cultural and biological far exceeding
those of the past. What happens in these fields will depend
increasingly upon the nature of the goals set and the means
employed, provided that men succeed in extending wisdom
and conscience into this sphere. Here is an enormous new
field for a rethinking of the problems of human life and of
life in general from the bottom up, taking into consideration
everything that the past has taught us.

Muller: The reasons were given earlier for concluding that the
scientific and social advances of our present culture are tending to
produce a negative feedback upon our genetic structure, allowing —
and, in some respects, even encouraging — its deterioration: a kind
of natural selection in reverse. Luckily, however, our present culture
has also made us aware of this situation and has brought us knowledge
of evolution as a whole, as some of us have found at this series of
meetings.

As with the dangerous techniques placed in our hands by physics,
chemistry, mass media for thought control, and the means of deple-

238 ' ISSUES IN EVOLUTION

tion of our resource, we see that if we would retain the benefits of
civihzation, there can be no effective renunciation of our powers. In-
stead, we must meet all these difficulties by mustering greater fore-
sight and greater social responsibility in the use of our knowledge and
skills and in the further extension of our knowledge and self-control.

In genetics this means that, with a knowledge of biological evolu-
tion and actuated by a greater sense of responsibility to their succes-
sors, men will come to extend their social awareness to include not
only their contemporaries but also the next and succeeding genera-
tions. In learning, as they must, to control their numbers, men will also
become aware of the paramount importance of the genetic material
within them. A new kind of pride in reproduction will appear when
those persons burdened with more than the average share of genetic]
defects realize that their most valuable services will lie in restricting
the multiplication of their own genes and contributing to the com-?
munity in ways that are not directly genetic. Conversely, those per-1
sons more fortunately endowed will feel it their obligation to repro-
duce to more than the average extent. No one knows better than the
geneticist how uncertain is the knowledge of any given individual's
genetic constitution, how the effects of environment are interwoven
with heredity in molding every individual, and how randomness enters
into the determination of what genes any new individual shall have.
And no one knows better than the social scientist how vicious and self-
defeating would be any attempt at dictation in matters of reproduction.

What counts in evolution, however, is not the individual but the
general trend; for over-all selection in a given direction eventually
works, and consciously directed selection works much faster than
unconscious selection. The important thing, then, is the kind of trend.
Here the madness of the racists has taught the world by terrible ob-
ject lessons the dangers of egotism, ethnocentrism, and particularism.
One of the main antidotes to this is a better, more vivid teaching of
evolution, which emphasizes the fundamental unity of man and the
overriding importance of the species as a whole and underscores the
paramount values cherished by men the world over — especially, genu-
ine warmth of fellow feeling and a co-operative nature, depth and
breadth of intellectual capacity, moral courage and integrity, appre-
ciation of nature and art, and aptness of expression and communica-
tion. The exercise of these faculties has brought man to his present
state.

But most persons, if they are honest, will grant that these qualities
have never been in oversupply and that, as our culture advances, we
can make increasingly good use of a higher quality and quantity of
them. At the same time, the furtherance of specialized abilities de-

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 239

veloped in response to particular predilections, as for music, will help
enrich the whole. Unless men sink into the hands of mad or ignorant
dictators, there is, I think, no danger that in the over-all run they will
fail to recognize these fundamental values. After all, the same prob-
lem of what we should aim for appears when we educate our children.
Just as most of us are coming to recognize these same aims in educa-
tion, so we will naturally follow them also in genetics.

Nor is there a danger that these faculties can be too abundant. As
men learn better techniques and acquire better facilities for nurturing,
preserving, multiplying, and transferring their genetic material, both
male and female, they will not rest content with the primitive methods
of the past but will increasingly use their new reproductive powers to
further their ideals, even as they will use atomic energy to reach the
stars. They will take pride in having their children — whom they will
rightly regard as theirs — derived from the best reproductive cells
possible, some of which they deliberately "adopted" prior to preg-
nancy, while the children, thus more happily endowed on the average
than their parents, will love these parents that thus made them pos-
sible and raised them as their very own. With higher intelligence and
a more deep-rooted otherliness of character will come an increasing
range of foresight that can plan ahead to reaches far beyond that
horizon of ours that in the direction of the future is so very near us
and so limited.

As for our horizon in the opposite direction, we have at least
glimpsed the grand panorama of the four to five billion years of evo-
lution in the past, and so we know of what seeming miracles the plas-
ticity of protoplasm — or DNA if you like — is ultimately capable. It
is true that, with our present genetic basis, culture alone has carried
us very far and can carry us very much farther and, wisely developed,
can give every man a fitting place under the sun. It is also true that,
even with human aid, biological progress is far slower than that of
culture. But the total advance is not the sum of these two; it is more
like the product or even the exponent. Even as our own culture could
not mean very much to the most superior ape, the culture of a mere
million years from now will be so rich and advanced in its poten-
tialities of experience and accomplishment that in it we, with our
genetic constitution of today, would be like imbeciles in the palace.
And so I believe that not only our cultural but also our biological
evolution will go on to now undreamed-of heights. Each of these two
processes will reinforce the other and with a feedback that is not only
again positive but also enormously more effective.

Adams: This has been an eloquent statement by a very eminent
geneticist, and I certainly do not dispute its biological basis. But, on

240 • ISSUES IN EVOLUTION

the eve of this second century after Darwin, I should like to question
the social consequences of Muller's views.

MuUer's statement just now, like earlier statements on this panel,
concerned overpopulation and referred to a population explosion. A
counterpoint was developed between greed or reproduction and need.
Unless disagreement is voiced, this emphasis might very well produce
a belief that the central focus of an evolutionistic approach must be
control of population. (Incidentally, I am not concerned here with the
moral objections that might be raised to this plan; others certainly
are.)

The first defect in this view of overpopulation as our central prob-
lem is that it casts an aura of unjustified pessimism on all efforts to
achieve economic betterment and development before some nirvana
of population level is reached. The generalization that an increasing
rate of per capita productivity is impossible in impoverished and
densely populated countries simply does not correspond with the facts,
as P. T. Bauer and B. S. Yamey have persuasively argued.

A second defect in this undue concern with overpopulation is that
it tends to focus attention on certain quantitative aspects of economic
growth, particularly on a simple index of output per head. This ig-
nores the crying need over much of the world for qualitative changes
making improved subsistence possible, for such things as land reform,
stimulation of investments, and improvements in planning.

Most serious students will agree that rising population is a very
serious problem. I should be the last to say that we should not be con-
cerned about this; but it would be a mistake to express our concern
about the future only, or mainly, in terms of this single axis of growth.

[Steward: I am grateful for the opportunity to comment on our
fifteenth point, which properly expresses concern about possible mis-
uses of knowledge in controUing the future and, conversely, impUes
optimism, "provided that men succeed in extending wisdom and con-
science into this sphere." I doubt whether many of my colleagues
would subscribe to the implication that a scientist, by virtue of his
knowledge or conscience, should dictate man's destiny.

As an individual citizen, any scientist has the undeniable right to
advocate what he pleases, but he should not foster the illusion that his
goals are external to himself and his time and can be scientifically
validated. The evidence of cultural evolution seems clearly to indicate
that goals and procedures have cultural determinants. It would, there-
fore, be extraordinarily dangerous to place our future in the hands
of men who claim wisdom and conscience. Hitler and Genghis Khan
undoubtedly claimed to be wise; and since all men are shaped by their
cultures, in their own lights they had great conscience.

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 241

The role of the scientist is to analyze and interpret; and there is
still much to learn about the dynamics of cultural evolution. The many-
faceted views of this panel, stimulating as they are, indicate the very
great disagreement about the nature of cultural evolution. This dis-
cussion has only tangentially touched upon the problem of cause-and-
effect relationships that might permit even tentative forecasts into the
fairly near future.

The present understandings of cultural science are most pertinent
to what we might call "negative goals." As scientists we may hope to
throw some light on the ways to avoid a war of extermination or to
reduce the social stresses and frictions resulting from unequal distri-
bution of opportunity and material goods, from racial, ethnic, and re-
ligious prejudices, and from the neuroses and psychosomatic ills to
which the imbalances and conflicts of modern life contribute.

But until we know more about non-biological or exosomatic cultural
evolution, attempts to control cultural evolution through manipulation
of human genetics would be rash. I do not question a deleterious feed-
back of culture upon our genetic constitution, but this process ob-
viously has no bearing on the mechanisms of cultural evolution. In-
telligence may, in the long run, affect the rate of evolution, but I
know of no shred of evidence that it determines in any way whatever
the direction of evolution. Our distinguished geneticist has suggested
that fellowship, co-operation, moral courage and integrity, apprecia-
tion of nature and art, and aptness of expression and communication
are desirable human traits. One must agree. But, since each of these
qualities has meanings peculiar to its particular evolutionary stage
and social type, he surely cannot mean that they are genetically deter-
mined.

As for ills of the human flesh, many of them genetically based, it
is heartwarming that a blind poet, a deaf musician, a consumptive
novelist, and a hunchback physicist have contributed so much to our
intellectual heritage as to be classed as geniuses. Since modern medi-
cine now keeps most people alive to fulfil their humble — or exalted —
destinies and the principal killers of today are largely cancer and heart
disease, an all-out plan of eugenics would have to deprive nearly every-
one of offspring.]

Huxley: I think I ought to take up what Adams has said, and I
should also like to comment on some of the remarkable points my
old friend and colleague Muller raised in his eloquent and even pro-
phetic speech.

I have been deeply interested in the population problem. Of course,
it is not the only problem we ought to concentrate on; but I don't
think Adams' point about not bothering with economic development

242 ■ ISSUES IN EVOLUTION

until we have dealt with population is well taken. The two are tied to-
gether. Coale and Hoover's careful study, for instance, has shown that
India cannot achieve industrialization unless it halves its birth rate in
the next thirty or forty years. Furthermore, overrapid population
growth is destroying many of the world's qualitative resources — re-
sources for enjoyment as well as material resources for use — but I do
not have time to go into that now.

I appreciated Polak's admirable phrase that we must learn to adapt
the future to our ideal aims. One of man's unique qualities is that in
his evolution he is able to preadapt to the future. Polak has reformu-
lated this fact in a striking way.

When one looks at the future in the broadest possible way, it is
important always to distinguish two viewpoints: the most ultimate one
that you can consider — the ideals that Polak stresses — and the nearer
view, of the immediate problems. Each age has its own particular
problems. The overproduction of people was not a problem three cen-
turies ago; the overproduction of cars or other products was not a
problem fifty years ago; atomic war was not a problem twenty years
ago.

But when you look at psychosocial evolution in the long view, you
must consider both its material and its mental aspects. Muller quite
rightly stressed the long-term importance of genetic improvement.
We must not neglect the important and equally essential improvement
of purely psychosocial organs — the organization of "mentifacts," to
use Kroeber's delightful word. We have to create a social organiza-
tion that will enable the world to function as a unity. We have to create
a world based on science, but not one entirely technological. It must
be naturahstic and yet involve moral and rehgious values. We have
to create art and literature to express our new world and a new kind
of educational system to prepare the new generations to take their place
in it.

But to return to Muller's main thesis, it is clear that, although cul-
tural change has, on the whole, become predominant in psychosocial
evolution, genetic change has been going on from the beginning.
Muller brought out the fascinating point that, in its early stages, there
was positive feedback between genetics and culture but that now the
feedback has become largely negative. Undoubtedly a great deal of
natural selection is going on, in the sense that different types of people
are multiplying at different rates; and this appears to be, on balance,
dysgenic, so that we ought to do something about it. Our aim, of
course, should be to substitute some kind of conscious eugenic selec-
tion. I should like to emphasize that we shall have plenty of material
to work with. In the human species there is an enormous range of

PANEL FIVE: SOCIAL AND CULTURAL EVOLUTION • 243

variation, providing excellent opportunities for selection. Thus I en-
tirely agree with Muller's main contention — that when we have solved
our immediate problems, we should give most attention to improving
our genetic heritage.

Kluckhohn: Obviously (but this is a good thing, too), just at the
point when all of us have something to say and would like to speak,
we must stop. I think it is appropriate that we stop with the man who
has perhaps played a more central role than anyone else in this whole
Celebration.

Before today's session I had been instructed by my betters to give
a summary, and I duly started to take some notes today; but I see it
is completely beyond my capacity. I shall make just one statement
about it, which is what Simpson, in his great book, says about the
process of evolution in general: "There is both order and disorder in
it."

SOL TAX

CONCLUSION

Yesterday noon I was told that the newspapers would appreciate ad-
vance copies of these concluding remarks. With four sessions out of
five finished, why couldn't I write this speech? This reminds one of
the man who cashed a check for one hundred dollars and asked for
it in one-dollar bills. The teller in the bank suggested he count his
money, and dutifully he began, "One, two, three, four, five — thirty-
five, thirty-six, thirty-seven — it's right so far, so it's probably right the
rest of the way," and he stopped counting. After all, it was a local
newspaper that headlined the election of Thomas Dewey as president
of the United States.

The fact is that this is not a wrestling match that was fixed in ad-
vance. We knew each other's papers and general points of view, of
course, but not how we stood on these issues for discussion. The panel-
ists became acquainted during these last days and ironed out some
differences before coming to this stage. This made the discussion more
useful: semantics and misunderstandings were for the most part put
to one side.

Last Tuesday afternoon, in introducing these panels, I said: "Charles
Darwin broke through a tremendous fog, and one hundred years ago
this very day gave us a new understanding and perspective, on the
basis of which we have done a hundred years of fruitful research. The
tremendous knowledge gained in these hundred years of science we
hope this week to summarize and synthesize. But, more than that, I
at least have some hope, or fond illusion, that on this occasion and
in this hall we can take a new, great step forward to begin a second
century of understanding ourselves and our cosmos that will do justice
to our heritage and give hope for our future."

All of us realize that we have gone far to summarize and to syn-
thesize our present knowledge of evolution. Never before have so many
minds from so many diverse specialties been put so intensively to such
a task. At the same tune, clearly, nobody expects me at this moment
to summarize the summary or synthesize the synthesis. This will rather
be done in the years to come by each of us and by many of you — and by
readers of the books that will come out of this Centennial. We shall

245

246 • ISSUES IN EVOLUTION

all do it differently and from different perspectives, for that is the way
of science.

In the process of the growth of scientific knowledge, specialization
plays the part of sexual difference. As there would be no purpose in
sex if there were no mating, so science requires that our different knowl-
edge be brought together so that selection can act on the new recom-
binations. Only time will tell just how important is the event we have
here witnessed. But just as one hundred years ago there was full ap-
preciation that the publication of the Origin of Species was an event
for history, so one feels that history will take a new turn when it leaves
this room.

So that these do not seem the empty words that are spoken politely
at the end of a meeting, let me briefly sketch — as an example — how
this meeting has begun to change my own thinking.

To an anthropologist, biological evolution is taken for granted, but,
generally speaking, we believe — or have believed — that the shift from
somatic genetic evolution to psychosocial or cultural evolution is a
change as great as that from the inorganic evolution of the universe
to the evolution of life. The means of cultural evolution by symboling,
as White wants us to call them, extrasomatic as these are, are so dif-
ferent that the concepts of biological evolution seemed not to be very
useful. At best, the concepts of biology, like natural selection, seemed
to be analogies or even figures of speech, without real meaning or valid-
ity for evolution in the human phase.

After this week, it seems to me that, while the difference in the
mechanisms of growth are never to be minimized, there is, neverthe-
less, a larger view in which human society and culture are seen again
as part of the natural order and subject to the same laws of evolution
as the rest of nature.

In our third panel, for instance, there was a suggestion by Wadding-
ton that started a whole new train of thought in my mind. He talked
about the biological function of passing on information from one gen-
eration to the next, which is done genetically at some levels but in
man, for the most part, occurs socially. In fact, it is my understand-
ing that no culture is passed through the chromosomes. I am only
saying that information in the sense that Waddington was using it in-
cludes genetic characters as well as sociocultural characters. But in
all cases the receiving mechanism is as important as the mechanisms
for transmission of "information." Since humans transmit most in-
formation by means of language and social behavior rather than di-
rectly through the chromosomes, the species could not survive without
some appropriate receiving mechanism. Part of this receiving mech-
anism in humans is the predisposition of a child to believe his elders

CONCLUSION ■ 247

and to respect them. Later, he can doubt and select, but there must
be transmission before there can be selection.

The predisposition to believe must be a biological thing and subject
to processes like natural selection. So is the later ability to doubt and
to select. Men as individuals need both in order to survive. Human
communities have built into them the mechanisms both of continuity
and of change.

A human society in a most significant sense is able to control its
own destiny. I have felt that culture freed us from our biological base
and separated us from our animal cousins, but it becomes clearer
now that this ability is in a broader sense a biological mechanism
serving a biological need. Polak argued this morning for the unity of
all life in some ability to foresee the future; a rose, too, chooses its
destiny. I think I follow Huxley's denial. I rather see the unity in man's
free will as a mechanism in our own survival that in a large sense
should be thought of as biological.

This broader view of man as part of a single evolutionary system,
at least of this planet, comes to us — or at least to me — as we bring
together our various branches of knowledge. It is for each of us as
individuals to take account of new knowledge and relate it to our own
personal philosophies.

This afternoon some of us will hear a discussion of the conflict of
science and religion. I cannot anticipate the result, but I would hope
that in the next hundred years our religious leaders may come to quote
the Gospel as saying, "Render unto science that which belongs to sci-
ence," and our scientists will leave it to all of us to interpret and use
facts as part of a human document of which both introduction and
conclusion are necessarily enduring cultural values.

Whether or not this theological debate moves in the second hundred
years to a new level, our meeting this week should help us, at least
in America, to turn the corner in accepting evolution as a fact. I sup-
pose that there are no schools where it is taught that the earth is flat
as a pancake; I wonder if there are any classrooms where students are
told that there is a "theory" that the earth is a globe and that it may
not be true. But perhaps most of our schools still teach evolution, not
as a fact, but as only one alternative among explanations of how the
world has come to be what it is. No matter what gets done about our
religious beliefs, this particular phenomenon must now come to an
end. We cannot deal with the difficult problems of the world unless
our education takes account of demonstrated empirical fact.

A gentleman of the press during our meeting asked me to say some-
thing now about the future of the evolution of man. Putting together
what we have learned this week, including this morning, gives us a

248 • ISSUES IN EVOLUTION

fairly clear answer: If man will build on knowledge instead of preju-
dice; if our society will heed Muller's advice this morning to reward
those who look for the good of the whole rather than to their selfish
advantage (but not necessarily anything specific that Muller has said
this morning) — if we do these things, which it is in our power to do,
then and only then are we likely to come out of this alive.

Is it possible, one hopefully asks, that this week will become a turn-
ing point in human history to which we are witnesses? My family and
I happen to live in the house where Enrico Fermi lived during the
war. That great turning point in human technology — the first nuclear
reaction — occurred a pistol shot from where we now sit. Could we
by setting in motion here the steps that will turn our ingenuity to the
survival instead of the destruction of the species, make a new turning
point in history? One still fondly hopes.

SIR JULIAN HUXLEY

THE EVOLUTIONARY VISION

Future historians will perhaps take this Centennial week as epitomiz-
ing an important critical period in the history of this earth of ours —
the period when the process of evolution, in the person of inquiring
man, began to be truly conscious of itself. This is, so far as I am aware,
the first time that authorities on the evolutionary aspects of the three
great branches of scientific study — the inorganic sciences, the life-
sciences, and the human sciences — have been brought together for mu-
tual criticism and joint discussion. We participants who are assembled
here, some of us from the remotest parts of the globe, by the magnifi-
cently intelligent enterprise of the University of Chicago, include repre-
sentatives of astronomy, physics, and chemistry; of zoology, botany,
and paleontology; of physiology, ecology, and ethology; of psychology,
anthropology, and sociology. We have all been asked to contribute
an account of our knowledge and understanding of evolution in our
special fields to the Centennial's common pool, to submit our contribu-
tions to the criticism and comments of our fellow participants in quite
other fields, to engage in pubHc discussion of key points in evolutionary
theory, and to have our contributions and discussions published to the
world at large.

This is one of the first public occasions on which it has been frankly
faced that all aspects of reality are subject to evolution, from atoms
and stars to fish and flowers, from fish and flowers to human societies
and values — indeed, that all reality is a single process of evolution.
And ours is the first period in which we have acquired sufficient knowl-
edge to begin to see the outline of this vast process as a whole.

Our evolutionary vision now includes the discovery that biological
advance exists, and that it takes place in a series of steps or grades,
each grade occupied by a successful group of animals or plants, each
group sprung from a pre-existing one and characterized by a new and
improved pattern of organization.

SIR JULIAN HUXLEY delivered this Darwin Centennial Convocation address
on Thanksgiving Day, November 26, 1959. Another essay, "The Emergence of
Darwinism," appears in a companion volume, published earlier this year — Evolution
After Darwin. 1. The Evolution of Life, pp. 1-21.

249

250 • ISSUES IN EVOLUTION

Improved organization gives biological advantage. Accordingly, the
new type becomes a successful or dominant group. It spreads and mul-
tiplies and differentiates into a multiplicity of branches. This new bio-
logical success is usually achieved at the biological expense of the
older dominant group from which it sprang or whose place it has
usurped. Thus the rise of the placental mammals was correlated with
the decline of the terrestrial reptiles, and the birds replaced the ptero-
saurs as dominant in the air.

Occasionally, however, when the breakthrough to a new type of
organization is also a breakthrough into a wholly new environment,
the new type may not come into competition with the old, and both
may continue to coexist in full flourishment. Thus the evolution of
land vertebrates in no way interfered with the continued success of the
teleost bony fish.

The successive patterns of successful organization are stable pat-
terns: they exemplify continuity and tend to persist over long periods.
Reptiles have remained reptiles for three hundred million years: tor-
toises, snakes, lizards, and crocodiles are all still recognizably reptilian,
all variations on one organizational theme.

It is difficult for life to transcend this stability and achieve a new
successful organization. That is why breakthroughs to new dominant
types are so rare — and also so important. The reptilian type radiated
out into well over a dozen important groups or orders; but all of them
remained within the reptilian framework except two, which broke
through to the new and wonderfully successful patterns of bird and
mammal.

In the early stages, a new group, however successful it will eventu-
ally become, is few and feeble and shows no signs of the success that
it may eventually achieve. Its breakthrough is not an instantaneous
matter but has to be implemented by a series of improvements which
eventually become welded into the new stabilized organization.

With mammals, there was first hair, then milk, then partial and
later on full-temperature regulation, then brief and finally prolonged
internal development, with evolution of a placenta. Mammals of a
small and insignificant sort had existed and evolved for over a hun-
dred million years before they achieved a full breakthrough to their
explosive dominance in the Cenozoic.

Something very similar occurred during our own breakthrough from
mammalian to psychosocial organization. Our prehuman ape ances-
tors were never particularly successful or abundant. There was not
just one "missing link" between them and us. For their transformation
into man a series of steps was needed. Descent from the trees; erect pos-
ture; some enlargement of brain; more carnivorous habits; the use and

HUXLEY: THE EVOLUTIONARY VISION ■ 251

then the making of tools; further enlargement of brain; the discovery
of fire; true speech and language; elaboration of tools and rituals. These
steps took the better part of half a million years: it was not until less
than a hundred thousand years ago that man could begin to deserve
the title of dominant type and not until less than ten thousand years
ago that he became fully dominant.

After man's emergence as truly man, the same sort of thing con-
tinued to happen, but with an important difference. Man's evolution is
not biological but psychosocial; it operates by the mechanism of cul-
tural tradition, which involves the cumulative self-reproduction and
self-variation of mental activities and their products. Accordingly,
major steps in the human phase of evolution are achieved by break-
throughs to new dominant patterns of mental organization, of knowl-
edge, ideas, and beliefs — ideological instead of physiological or bio-
logical organization.

There is a succession of successful idea-systems instead of a suc-
cession of successful bodily organizations. Each new, successful idea-
system spreads and dominates some important sector of the world, un-
til it is superseded by a rival system or itself gives birth to its successor
by a breakthrough to a new organization-system of thought and belief.
We need only think of the magic pattern of tribal thought; the god-
centered medieval pattern, organized round the concept of divine
authority and revelation; and the rise in the last three centuries of
the science-centered pattern, organized round the concept of human
progress, but progress somehow under the control of supernatural Au-
thority. In 1859, Darwin opened the passage leading to a new psycho-
social level, with a new pattern of ideological organization — an evolu-
tion-centered organization of thought and belief.

Through the telescope of our scientific imagination, we can discern
the existence of this new and improved ideological organization; but
its details are not clear, and we can also see that the necessary steps
upward toward it are many and hard to take.

Let me change the metaphor. To those who did not deliberately shut
their eyes or who were not allowed to look, it was at once clear that
the fact and concept of evolution was bound to act as the central germ
or living template of a new dominant thought organization. And in
the century since the Origin of Species, there have been many attempts
to understand the implications of evolution in many fields, from the
affairs of the stellar universe to the affairs of men, and to integrate the
facts of evolution and our knowledge of its processes into the over-all
organization of our general thought.

All dominant thought organizations are concerned with the ultimate,
as well as with the immediate, problems of existence or, I should rather

252 • ISSUES IN EVOLUTION

say, with the most ultimate problems that the thought of the time is
capable of formulating or even envisaging. They are all concerned
with giving some interpretation of man, of the world which he is to
live in, and of his place and role in that world — in other words, some
comprehensible picture of human destiny and significance.

The broad outlines of the new evolutionary picture of ultimates are
beginning to be visible. Man's destiny is to be the sole agent for the
future evolution of this planet. He is the highest dominant type to be
produced by over two and a half billion years of the slow biological
improvement effected by the blind opportunistic workings of natural
selection; if he does not destroy himself, he has at least an equal stretch
of evolutionary time before him to exercise his agency.

During the later part of biological evolution, mind — our word for
the mental activities and properties of organisms — emerged with
greater clarity and intensity and came to play a more important role
in the individual lives of animals. Eventually it broke through, to be-
come the basis for further evolution, though the character of evolution
now became cultural instead of genetic or biological. It was to this
breakthrough, brought about by the automatic mechanism of natural
selection and not by any conscious effort on his own part, that man
owed his dominant evolutionary position.

Man is therefore of immense significance. He has been ousted from
his self-imagined centrality in the universe to an infinitesimal location
in a peripheral position in one of a million of galaxies. Nor, it would
appear, is he likely to be unique as a sentient being. On the other hand,
the evolution of mind or sentiency is an extremely rare event in the
vast meaninglessness of the insentient universe, and man's particular
brand of sentiency may well be unique. But in any case he is highly
significant. He is a reminder of the existence, here and there, in the
quantitative vastness of cosmic matter and its energy equivalents, of
a trend toward mind, with its accompaniment of quality and richness
of existence — and, what is more, a proof of the importance of mind
and quality in the all-embracing evolutionary process.

It is only through possessing a mind that he has become the domi-
nant portion of this planet and the agent responsible for its future evo-
lution; and it will be only by the right use of that mind that he will be
able to exercise that responsibility rightly. He could all too readily be
a failure in the job; he will succeed only if he faces it consciously and
if he uses all his mental resources — of knowledge and reason, of unagi-
nation, sensitivity, and moral effort.

And he must face it unaided by outside help. In the evolutionary
pattern of thought there is no longer either need or room for the super-
natural. The earth was not created; it evolved. So did all the animals

HUXLEY: THE EVOLUTIONARY VISION • 253

and plants that inhabit it, including our human selves, mind and soul
as well as brain and body. So did religion. Religions are organs of psy-
chosocial man concerned with human destiny and with experiences of
sacredness and transcendence. In their evolution, some (but by no
means all) have given birth to the concept of gods as supernatural
beings endowed with mental and spiritual properties and capable of
intervening in the affairs of nature, including man. Such supernaturally
centered religions are early organizations of human thought in its inter-
action with the puzzling, complex world with which it has to contend
— the outer world of nature and the inner world of man's own nature.
In this, they resemble other early organizations of human thought con-
fronted with nature, like the doctrine of the Four Elements, Earth,
Air, Fire and Water, or the Eastern concept of rebirth and reincarna-
tion. Like these, they are destined to disappear in competition with
other, truer, and more embracing thought organizations which are
handling the same range of raw or processed experience — in this case,
with the new reUgions which are surely destined to emerge on this
world's scene.

Evolutionary man can no longer take refuge from his loneliness in
the arms of a divinized father-figure whom he has himself created, nor
escape from the responsibility of making decisions by sheltering under
the umbrella of Divine Authority, nor absolve himself from the hard
task of meeting his present problems and planning his future by relying
on the will of an omniscient, but unfortunately inscrutable. Provi-
dence.

On the other hand, his loneliness is only apparent. He is not alone
as a type. Thanks to the astronomers, he now knows that he is one
among the many organisms that bear witness to the trend toward
sentience, mind, and richness of being, operating so widely but so
sparsely in the cosmos. More important, thanks to Darwin, he now
knows that he is not an isolated phenomenon, cut off from the rest
of nature by his uniqueness. Not only is he made of the same matter
and operated by the same energy as all the rest of the cosmos, but, for
all his distinctiveness, he is linked by genetic continuity with all the
other Hving inhabitants of his planet. Animals, plants, and micro-
organisms, they are all his cousins or remoter kin, all parts of one
single evolving flow of metabolizing protoplasm.

Nor is he individually alone in his thinking. He exists and has his
being in the intangible sea of thought which Teilhard de Chardin has
christened the "noosphere," in the same sort of way that fish exist and
have their being in the material sea of water which the geographers in-
clude in the term "hydrosphere." Floating in the noosphere there are,
for his taking, the daring speculations and aspiring ideals of man long

254 ■ ISSUES IN EVOLUTION

dead, the organized knowledge of science, the hoary wisdom of the
ancients, the creative imaginings of all the world's poets and artists.
And in his own nature there is, waiting to be called upon, an array of
potential helpers — all the possibilities of wonder and knowledge, of
delight and reverence, of creative belief and moral purpose, of pas-
sionate effort and embracing love.

Turning the eye of an evolutionary biologist upon this situation, I
would compare the present stage of evolving man to the geological
moment, some three hundred million years ago, when our amphibian
ancestors were just establishing themselves out of the world's water.
They had created a bridgehead into a wholly new environment — no
longer buoyed up by water, they had to learn how to support their own
weight; debarred from swimming with their muscular tail, they had to
learn to crawl with clumsy limbs. The newly discovered realm of air
gave them direct access to the oxygen they needed to breathe, but it
also threatened their moist bodies with desiccation. And though they
managed to make do on land during their adult lives, they found them-
selves still compulsorily fishy during the early part of their lives.

On the other hand, they had emerged into completely new freedoms.
As fish, they had been confined below a bounding surface; now the air
above them expanded out into the infinity of space. Now they were
free of the banquet of small creatures prepared by the previous hun-
dred million years of life's terrestrial evolution. The earth's land surface
provided a greater variety of opportunity than did its waters and,
above all, a much greater range of challenge to evolving life. Could
the early Stegocephalians have been gifted with imagination, they
might have seen before them the possibility of walking, running, per-
haps even flying over the earth; the probability of their descendants
escaping from bondage to winter cold by regulating their temperature
and escaping from bondage to the waters by constructing private ponds
for their early development; the inevitability of an upsurge of their dim
minds to new levels of clarity and performance. But meanwhile they
would see themselves tied to an ambiguous existence, neither one
thing nor the other, on the narrow moist margin between water and
air. They could have seen the promised land afar off, though but dunly
through their bleary, newtish eyes. But they would also have seen that,
to reach it, they would have to achieve many difiicult and arduous
transformations of their being and way of life.

So with ourselves. We have only recently emerged from the biologi-
cal to the psychosocial area of evolution, from the earthy biosphere into
the freedom of the noosphere. Do not let us forget how recently: we
have been truly men for perhaps a tenth of a million years — one tick
of evolution's clock; even as protomen, we have existed for under one

HUXLEY: THE EVOLUTIONARY VISION • 255

million years — less than a two-thousandth fraction of evolutionary
time. No longer supported and steered by a framework of instincts, we
try to use our conscious thought and purposes as organs of psycho-
social locomotion and direction through the tangles of our existence —
but so far with only moderate success and with the production of much
evil and horror, as well as of some beauty and glory of achievement.
We too have colonized only an ambiguous margin between an old
bounded environment and the new territories of freedom. Our feet still
drag in the biological mud, even when we lift our heads into the con-
scious air. But, unlike those remote ancestors of ours, we can truly see
something of the promised land beyond. We can do so with the aid of
our new instrument of vision — our rational, knowledge-based imagi-
nation. Like the earUest pre-Galilean telescopes, it is still a very primi-
tive instrument and gives a feeble and often distorted view. But, like
the early telescopes, it is capable of immense improvement and could
reveal many secrets of our noospheric home and destiny.

Meanwhile, no mental telescope is required to see the immediate
evolutionary landscape and the frightening problems which inhabit it.
All that is needed — but that is plenty! — is for us to cease being in-
tellectual and moral ostriches and take our heads out of the sand of
wilful bUndness. If we do so, we shall soon see that the alarming
problems are two-faced and are also stimulating challenges.

What are those alarming monsters in our evolutionary path? I would
list them as follows. The threat of superscientific war, nuclear, chemi-
cal, and biological; the threat of overpopulation; the rise and appeal
of Communist ideology, especially in the underprivileged sectors of
the world's people; the failure to bring China, with nearly a quarter
of the world's population, into the world organization of the United
Nations; the erosion of the world's cultural variety; our general pre-
occupation with means rather than ends, with technology and quantity
rather than creativity and quahty; and the revolution of expectation
caused by the widening gap between the haves and the have-nots, be-
tween the rich and the poor nations.

Today is Thanksgiving Day. But millions of people now living have
little cause to give thanks for anything. When I was in India this spring,
a Hindu man was arrested for the murder of his small son. He ex-
plained that his life was so miserable that he had killed the boy as a
sacrifice to the goddess Kali, in the hope that she would help him in
return. That is an extreme case. But let us remember that two-thirds
of the world's people are underprivileged — underfed, underhealthy,
undereducated — and that millions of them live in squalor and suffer-
ing. They have little to be thankful for, save hope that they will be
helped to escape from this misery. If we m the West do not give them

256 • ISSUES IN EVOLUTION

aid, they will look to other systems for help — or even turn from hope
to destructive despair.

We attempt to deal with these problems piecemeal, often half-
heartedly; sometimes, as with population, we refuse to recognize it
officially as a world problem (just as we refuse to recognize Com-
munist China as a world power). In reahty, they are not separate mon-
sters, to be dealt with by a series of separate ventures, however heroic
or saintly. They are all symptoms of a new evolutionary situation; and
this can be successfully met only in the light and with the aid of a new
organization of thought and belief, a new dominant pattern of ideas.

It is hard to break through the firm framework of an accepted
belief system and build a new acceptable successor, but it is necessary.
It is necessary to organize our ad hoc ideas and scattered values into
a unitive pattern, transcending conflicts and divisions in its unitary
web. Only by such a reconcifiation of opposites and disparates can
our belief-system release us from inner conflicts; only so can we gain
that peaceful assurance that wiH help unlock our energies for develop-
ment in strenuous practical action.

Somehow or other, we must make our new pattern of thinking
evolution-centered. It can give us assurance by reminding us of our
long evolutionary rise; how this was also, strangely and wonderfully,
the rise of the mind; and how that rise culminated in the eruption of
mind as the dominant factor in evolution and led to our own spectacu-
lar, but precarious, evolutionary success. It can give us hope by point-
ing to the eons of evolutionary time that lie ahead of our species if it
does not destroy itself or damage its own chances; by recalling how
the increase in man's understanding and the improved organization of
his knowledge have in fact enabled him to make a whole series of ad-
vances, such as control of infectious disease or efiiciency of telecom-
munication, and to transcend a whole set of apparently unbridgeable
oppositions, like the conflict between Islam and Christendom or that
between the seven Kingdoms of the Heptarchy; and by reminding us
of the vast stores of human possibility — of inteUigence, imagination,
co-operative good will — which still remain untapped.

Our new organization of thought — belief -system, framework of
values, ideology, caH it what you will — must grow and be developed
in the light of our new evolutionary vision. So, in the first place, it must,
of course, itself be evolutionary. That is to say, it must help us to think
in terms of an overriding process of change, development, and pos-
sible improvement; to have our eyes on the future rather than on the
past; to find support in the growing body of our knowledge, not in
fixed dogma or ancient authority.

Equally, of course, the evolutionary outlook must be scientific, not

HUXLEY: THE EVOLUTIONARY VISION • 257

in the sense that it rejects or neglects other human activities, but in
believing in the value of the scientific method for eliciting knowledge
from ignorance and truth from error and in basing itself on the firm
ground of scientifically established knowledge. Unlike most theolo-
gies, it accepts the inevitability and, indeed, the desirability of change,
and it advances by welcoming new discovery even when this conflicts
with old ways of thinking.

The only way in which the present split between religion and science
could be mended would be through the acceptance by science of the
fact and value of religion as an organ of evolving man and the accept-
ance by religion that religions do and must evolve.

Next, the evolutionary outlook must be global. Man is strong and
successful insofar as he operates in interthinking groups, which are
able to pool their knowledge and beliefs. To have any success in ful-
filling his destiny as the controller or agent of future evolution on
earth, he must become one single interthinking group, with one general
framework of ideas; otherwise his mental energies will be dissipated in
ideological conflict. Science gives us a foretaste of what could be. It
is already global, with scientists of every nation contributing to its ad-
vance; and, because it is global, it is advancing fast. In every field
we must aim to transcend nationalism, and the first step toward this is
to think globally — how could this or that task be achieved by interna-
tional co-operation rather than by separate action?

But our thinking must also be concerned with the individual. The
well-developed, well-patterned individual human being is, in a strictly
scientific sense, the highest phenomenon of which we have any knowl-
edge, and the variety of individual personalities is the world's highest
richness.

The individual need not feel just a meaningless cog in the social
machine or merely the helpless prey and sport of vast impersonal forces.
He can do something to develop his own personality, to discover his
own talents and possibilities, to interact personally and fruitfully with
other individuals. If so, in his own person, he is effecting an important
realization of evolutionary possibility: he is contributing his own per-
sonal quality to the fulfihnent of human destiny. He has assurance
of his own significance in the greater and more enduring whole of
which he is part.

I spoke of quality. This must be the dominant concept of our new
belief-system — quality and richness as against quantity and uniformity.

Though our new idea-pattern must be unitary, it need not and
should not impose a drab or boring cultural uniformity. A well-organ-
ized system, whether of thought, expression, social life, or anything
else, has both unity and richness. Cultural variety, both in the world

258 ■ ISSUES IN EVOLUTION

as a whole and within its separate countries, is the spice of life; yet
it is being threatened and indeed eroded away by mass production,
mass communications, mass conformity, and all the other forces
making for uniformization — an ugly word for an ugly thing! We have
to work hard to preserve and foster it.

One sphere where individual variety could and should be encour-
aged is education. In many school systems, under the pretext of so-
called democratic equality, variety of gifts and capacity is now actually
being discouraged. The duller children become frustrated by being
rushed too fast, the brighter become frustrated by being held back and
bored.

Our new idea-system must jettison the democratic myth of equality.
Human beings are not born equal in gifts or potentiaUties, and human
progress stems largely from the very fact of their inequality. "Free
but unequal" should be our motto, and diversity of excellence, not
conforming normalcy or mere adjustment, should be the aim of edu-
cation.

Population is people in the mass; and it is in regard to population
that the most drastic reversal or reorientation of our thinking has be-
come necessary. The unprecedented population explosion of the last
half -century has strikingly exemplified the Marxist principle of the
passage of quantity into quality. Mere increase in quantity of people is
increasingly affecting the quality of their lives, and affecting it almost
wholly for the worse.

Population increase is already destroying or eroding many of the
world's resources, both those for material subsistence and those —
equally essential but often neglected — for human enjoyment and fulfil-
ment. Early in man's history the injunction to increase and multiply
was right. Today it is wrong, and to obey it will be disastrous. The
Western world, the United States in particular, has to achieve the
difficult task of reversing the direction of its thought about population.
It has to begin thinking that we should aim — not at increase but at
decrease — certainly and quickly a decrease in the rate of population
growth and, in the long run equally certainly, a decrease in the abso-
lute number of people in the world, including our own countries.

The spectacle of explosive population increase is prompting us to
ask the simple but basic question What are people for? And we see
that the answer has something to do with their quality as human beings
and the quality of their lives and their achievements.

We must make the same reversal of ideas about our economic sys-
tem. At the moment (and again I take the United States as most repre-
sentative) our Western economic system (which is steadily invading

HUXLEY: THE EVOLUTIONARY VISION ■ 259

new regions) is based on expanding production for profit, and produc-
tion for profit is based on expanding consumption. As one writer has
put it, tlie American economy depends on persuading more people to
believe they want to consume more products.

But, like population explosion, this consumption explosion cannot
continue much longer; it is an inherently self-defeating process. Sooner,
rather than later, we must get away from a system based on artificially
increasing the number of human wants and set about constructing one
aimed at the qualitative satisfaction of real human needs, spiritual and
mental as well as material and physiological. This means abandoning
the pernicious habit of evaluating every human project solely in terms
of its utility — by which the evaluators mean solely its material utility
and especially its utility in making a profit for somebody.

Once we truly believe (and true belief, however necessary, is rarely
easy) — once we truly believe that man's destiny is to make possible
greater fulfilment for more human beings and fuller achievement by
human societies, utifity in the customary sense becomes subordinate.
Quantity of material production is, of course, necessary as the basis
for the satisfaction of elementary human needs — but only up to a
certain degree. More than a certain number of calories or cocktails or
TV sets or washing machines per person is not merely unnecessary but
bad. Quantity of material production is a means to a further end, not

an end in itself.

The important ends of man's life include the creation and enjoy-
ment of beauty, both natural and man-made; increased comprehen-
sion and a more assured sense of significance; the preservation of all
sources of pure wonder and dehght, hke fine scenery, wild animals m
freedom, or unspoiled nature; the attainment of inner peace and har-
mony; the feeling of active participation in embracing and endurmg
projects, including the cosmic project of evolution. It is through such
things that individuals attain greater fulfilment.

As for nations and societies, they are remembered not for their
wealth or comforts or technologies but for their great buildings and
works of art, their achievements in science or law or political philoso-
phy, their success in liberating human thought from the shackles of
fear and ignorance.

Although it is to his mind that man owes both his present dominant
position in evolution and any advances he may have made during his
tenure of that position, he is still strangely ignorant and even super-
stitious about it. The exploration of the mind has barely begun. It
must be one of the main tasks of the coming era, just as was the ex-
ploration of the world's surface a few centuries ago. Psychological

260 • ISSUES IN EVOLUTION

exploration will doubtless reveal as many surprises as did geographical
exploration and will make available to our descendants all kinds of
new possibilities of fuller and richer living.

Finally, the evolutionary vision is enabling us to discern, however
incompletely, the lineaments of the new religion that we can be sure
will arise to serve the needs of the coming era. Just as stomachs are
bodily organs concerned with digestion and involving the biochemical
activity of special juices, so are religions psychosocial organs of man
concerned with the problems of destiny and involving the emotion of
sacredness and the sense of right and wrong.

Religion of some sort is certainly a normal function of psychosocial
existence. It seems to be necessary to man. But it is not necessarily a
good thing. It was not a good thing when the Hindu I read about this
spring killed his son as a rehgious sacrifice. It is not a good thing that
religious pressure has made it illegal to teach evolution in Tennessee
because it conflicts with fundamentalist beliefs. It is not a good thing
that in Connecticut and Massachusetts women should be subject to
grievous suffering because Roman Catholic pressure refuses to allow
even doctors to give information on birth control even to non-Catho-
lics. It was not a good thing for Christians to persecute and even burn
heretics; it is not a good thing when communism, in its dogmatic-
religious aspect, persecutes and even executes deviationists.

The emergent religion of the near future could be a good thing. It
will believe in knowledge. It should be able to take advantage of the
vast amount of new knowledge produced by the knowledge explosion
of the last few centuries to construct what we may call its "theology" —
the framework of facts and ideas which provide it with intellectual
support; it should be able, with our increased knowledge of mind, to
define our sense of right and wrong more clearly so as to provide a
better moral support; it should be able to focus the feefing of sacredness
onto fitter objects, instead of worshiping supernatural rulers, so as to
provide truer spiritual support, to sanctify the higher manifestations of
human nature in art and love, in intellectual comprehension and as-
piring adoration, and to emphasize the fuller reahzation of life's possi-
bilities as a sacred trust.

Thus the evolutionary vision, first opened up to us by Charles Dar-
win a century back, illuminates our existence in a simple, but almost
overwhelming, way. It exemplifies the truth that truth is great and will
prevail, and the greater truth that truth will set us free. Evolutionary
truth frees us from subservient fear of the unknown and supernatural
and exhorts us to face this new freedom with courage tempered with
wisdom and hope tempered with knowledge. It shows us our destiny
and our duty. It shows us mind enthroned above matter, quantity sub-

HUXLEY: THE EVOLUTIONARY VISION • 261

ordinate to quality. It gives our anxious minds support by revealing
the incredible possibilities that have already been realized in evolu-
tion's past and, by pointing to the hidden treasure of fresh possibili-
ties that could be realized in its long future, it gives man a potent in-
centive for fulfilling his evolutionary role in the universe.

'ALL THINGS CONSIDERED"
A TELEVISION POSTSCRIPT

Announcer: A university draws together men and women con-
cerned with ideas and events. It provides a meeting place for the in-
formed and for the curious, for all engaged in man's pursuit of knowl-
edge. This evening the University of Chicago presents another in its
series of discussion programs on "All Things Considered." Tonight's
subject concerns "Issues in Evolution." The participants are Sir Julian
Huxley, biologist and writer and Visiting Professor at the University
of Chicago; Ilza Veith, Associate Professor, Departments of Medicine
and History; and Robert M. Adams, Assistant Professor in the Depart-
ment of Anthropology, and Research Associate in the Oriental Insti-
tute. Leading the discussion is Alec Sutherland, Director of Educa-
tional Broadcasting, the University of Chicago.

Sutherland: I should like to begin this evening with a personal
anecdote. About thirty years ago I invested a day's pay to buy a ticket
for a lecture in Glasgow; and at the end of this lecture, which was on
biology, there was the usual man in the audience who, in exchange
for his half-crown, wanted answers to two questions: What is uhi-
mate truth? and what was the lecturer going to do when we discov-
ered it? And the lecturer said, "I don't know what it is, and when we
discover it, I shall be out of a job." That particular lecturer is now
sitting at the opposite end of this table. I doubt if he remembers the
occasion very well, but I am sure he is still gainfully employed. Do
you remember that?

Huxley: I have no recollection of it, but I am delighted to learn
that I said such a good thing.

Sutherland: We have^been celebrating Darwin's centennial here,
and I should like to ask each of our participants what the impact of
the Centennial was on him.

Veith: I feel that the greatest impact on me was the exchange of
ideas with my fellow panelists and the opportunity to gauge the work

Educational station WTTW (Chicago, Channel 11) presented this television pro-
gram on the Tuesday following the Darwin Centennial Celebration, December 1,
1959.

263

264 ■ ISSUES IN EVOLUTION

they had done and to see that all of them are basically working in fields
related to evolution.

Adams: That comes rather close to my own reaction. Looking
back over the whole series of panels, I think the exchange was par-
ticularly important as one moved from the biological to the social and
cultural end of the spectrum into fields that have tended to use an
approach that is cautious, holistic, essentially differentiating, and
analytical. Those of us who were anthropologists came away with an
enhanced sense that evolution is continuous and that we are involved
with the same kinds of problems as biologists, zoologists, and psycholo-
gists. This forceful bringing home of the connection between general
theory and substantive studies was very important for me.

Huxley: I agree. This mixing up of persons from different disci-
plines in the discussions was a wonderful thing. Perhaps the most im-
portant was bringing together biologists and anthropologists, because
they have a great deal to learn from each other; but the physicists and
physiologists and biochemists also contributed to the fruitful mixing.
And we came to realize that all of us were interested from different
angles in this one over-all process that is called "evolution" and that
we had to achieve some unification of our thought about it.

Sutherland: All of you were concerned with evolution in rather
specialized ways. Have you any views on the effect of your discussions
on the lay public?

Veith: Simply judging from the behavior of the lay public attend-
ing our meetings, the interest must have been enormous. They came
in masses, stayed to the very end of each panel, and seemed com-
pletely lost in what was going on in the discussions.

Huxley: It was very remarkable. They even applauded at the end.

Veith: Another point is that the press reported the events that
went on in Mandel Hall; and from the reaction of the press we have
a definite impression that what was said was considered tremendously
important even by those members of the general public who were not
present but wanted to be informed.

Adams: Another aspect of the impact of the panels might be worth
bringing out here. Too often in the newspapers, on the radio, and also,
one would suspect, in the public's mind, research is identified with
some discrete and apparently infinitesimal finding, whereas here what
was being presented was an entire framework of research in a huge
area.

Huxley: I think that was extremely important. The first thing the
Celebration did, I am sure, was to convince a large number of people
that there was no point arguing about the theory of evolution. (By the
way, the Centennial was not supposed to commemorate the theory;

ALL THINGS CONSIDERED ■ 265

it commemorated an actual event, the publication of Darwin's book
On the Origin of Species by Means of Natural Selection.) It simply
is not just a theory any longer; it is a fact, hke the fact that the earth
goes around the sun and that the planets do all sorts of things. As
Adams said, the panels were pursuing the implications of this idea
in all sorts of fields, not in relation to any particular discovery, but in
working out gradually what evolution meant for different branches
of science. If it comes to a particular field, I think one of the high-
lights of the Celebration was Leakey's presence, with his new finds
from Africa. As was brought out very clearly in Panel Three, we can
no longer talk about the "missing link"; there isn't such a thing. There
was a rapid passage from the prehuman to the human, but it took
place in a series of steps over a considerable period of time. The other
point that I think was brought home to the people who attended the
panels was that you can no longer talk about creation. Animals, plants,
and human beings evolved; they were not created in the bibhcal sense.

Sutherland: We have talked about Panel Three. What were the
rest of the panels. Dr. Veith? You had a role in planning them.

Veith: Perhaps it would be best simply to read the titles of the
various panels. I think they are descriptive enough. The first panel
dealt with the origin of life; the second, with the evolution of life; and
the third — the one about which Sir Julian has been talking — dealt
with man as an organism. The fourth panel, with which I was most
closely associated, dealt with the evolution of mind; and the final one,
with which Mr. Adams was associated, concerned social and cultural
evolution.

Sutherland: I should like to hear something about the origin of
life.

Huxley: There, again, I think what happened was very important.
This was the first occasion on which at a pubfic celebration the origin
of life had become a topic of really scientific discussion. Twenty years
ago we could not have discussed it scientifically. Now, thanks to the
work of Urey, Oparin, Haldane, and others, it is a subject that can be
discussed scientifically. We can begin to see what steps were taken in
the passage from the non-Hving to the living, and we can suggest lines
of experimental approach to test our theories. I think this first panel
was a very important education for the panelists as well as for the
general public.

Sutherland: What about the evolution of life?

Huxley: Of course, that is the field in which most work has been
done; after all, it is the area where the theory of evolution was
launched. I think two main points emerged from the discussion. First,
that all reputable evolutionary biologists now agree that the evolution

266 ■ ISSUES IN EVOLUTION

of life is directed by the process of natural selection, and by nothing
else, and that they have demonstrated its happening. Second, that the
course of evolution involves three main subprocesses: the process of
branching into different forms; the process of biological improvement
of the different lines; and the process of stabilization, by which a suc-
cessful type somehow crystallizes out and persists over many millions
of years, unless it is superseded by one of the rare accidental break-
throughs to another type.

Adams: I had the feeling that Panel Two came very close to being
the central focus of the whole series; we moved out in various direc-
tions from the processes and generalizations that were seen there in
their clearest and broadest forms. It was interesting to see the extent
to which members of other panels picked up terminology from the
background papers for this panel and tried to use it in a different con-
text.

Sutherland: Where did evolution of mind fit into this?

Veith: Actually, evolution of mind fits anywhere; because the mind
is part of any human and non-human function, it would have fit into
any of the panels. I think it was quite accidental that it happened to
be Panel Four. We began with the clear statement and the clear
thought that Darwin's work has had a tremendous impact on the be-
havioral sciences. All those who are in any way connected with the
study of behavior of the mind — or the study of the brain, since mind
is a very difficult thing to define — have enriched or added to Dar-
winian principles and Darwinian reasoning. We proceeded on the
assumption that the evolution of the mind and the faculty of mind
and behavior can be studied as can be any other organic function.
Several of our participants were particularly interested in the study
of the mind in animals, which has now received the special designation
ethology — the study of animal behavior. Many signs of mental func-
tion appear in the animal world. Emotional attitudes have been dis-
covered in animals. Learning by imitation and even value systems
have been recognized as existing in animal groups. Tinbergen, one of
the leading ethologists, gave particularly good examples of these value
systems among animals. But it is believed or assumed that animals
do not yet possess self-awareness. We do not know this, and we cannot
judge it; but we must assume it, because there is no evidence of self-
awareness.

Sutherland: What do you mean by "self-awareness"?

Veith: Giving expression to self-consciousness. In man, as we all
know, there is self-consciousness. And what sets man apart from
animals more than any other single quahty is the ability to use Ian-

ALL THINGS CONSIDERED • 267

guage. This step was one of those breakthroughs to which Sir Julian
referred earlier. It is one of the tremendously important steps that set
one group apart from another.

One point that was touched on by Panel Four but not discussed in
much detail is the appearance of maladaptation. Did maladaptation
set in with the beginning of language? How is it evident in animals?
What do animals do in case of maladaptation?

Huxley: Maladaptation is evident when either natural or psycho-
logical selection steps in to try to correct it, isn't it? I think there are
many instances of maladaptation, both physical and mental, in lower
animals.

Veith: I was particularly interested in mental maladaptation.

Huxley: That was one of the points that did not emerge very
clearly, but Tinbergen did bring out a little about it. A great deal of
animal behavior — lor instance, the courtship behavior of birds — is
the result of conflict — if you like to call it so — between two different
impulses: the impulse to attack and drive away the opposite sex, and
an impulse to approach or to run away, and so on. There is a con-
flict, but it is resolved in the behavior.

Veith: Tinbergen gave another example of maladaptation in an
animal group, where other animals attempted to bring the maladapted
individual back into the fold.

Huxley: I was glad that the title "Evolution of Mind" was used
for Panel Four. After all, Darwin himself, who really started the com-
parative study of mind and so of modern ethology, frankly recognized
the existence of mental (subjective) functions by calling his book The
Expression of the Emotions in Man and Animals. I think Panel Four
brought out, first, that one must not shy away from using the term
"mind," because it is not only perfectly justifiable but scientifically
necessary to extrapolate mind downward from man into animals.
Second, that mind emerged during biological evolution and that, since
all new phenomena in biological evolution appear to be the result of
natural selection, which works by differential advantage, the mental
or subjective aspect of behavior must therefore have some biological
advantage or value. And a third point that emerged was that mental
phenomena in animals can be just as unlike mental phenomena in
man as many physical structures in animals are unlike those in man.
Language among bees, for instance, depends on sensitivity to the
plane of polarized fight and on an ability to appreciate the significance
of dances. Again, the extraordinary phenomenon of imprinting does
not occur in man, or at least occurs only to a very slight degree.

Veith: I was particularly interested in Tinbergen's example of the

268 ' ISSUES IN EVOLUTION

titmice in England which started opening milk bottles by pecking
through the paper tops and apparently were able to communicate
to each other the message that this could be done.

Huxley: Some sort of imitation was involved — learning by follow-
ing an innovator — but not communication in the strict sense.

Sutherland: I should like to move on to your preoccupation in
this field, Dr. Adams. Where does the anthropologist abut on this?

Adams: I think there are suggestions of an interesting shift in the
position of the anthropologists at the symposium. The initial reaction
of at least some of us was one of uncertainty about finding anything
in common to talk about with representatives of other disciplines. But
a whole series of themes emerged that I am sure will preoccupy us for
a long time to come. One such theme was the element of continuity in
evolution. As man evolves, he superadds culture to his genetic equip-
ment, and by this new addition he is enabled to adapt in a whole series
of much more effective and complex ways — to spread himself over
the entire globe, to construct very complex societies, and, in fact, fre-
quently to direct the evolution of species all around him. Human so-
cieties are adaptive mechanisms; they have to be understood as having
an evolutionary role rather than as uniquely human creations that are
not to be compared with the evolutionary development of other or-
ganisms.

Two other themes were very insistently brought in upon those of
us who are anthropologists. One is that evolutionists deal not with
events but with processes. This is a term we shall have to rely upon
much more; it reorients the whole basis of inquiry, in a direction in
which we can do much more productive work. Second — and this is
most important to me — the importance throughout biology of the no-
tion of adaptive radiation, characterizing successive grades of de-
velopment, is directly applicable to the materials with which an an-
thropologist deals, beginning with men living in caves and small groups
and moving on through sedentary villages to full-scale civilizations.
We have usually been too preoccupied with our more limited fields of
individual concern to see that a cumulative progression achieved in
disjunctive steps is fundamental. Perhaps, for this reason, we have
sometimes failed to recognize our common links with our colleagues
who are evolutionary biologists.

Huxley: Exactly the same thing happened in biology. People were
so preoccupied with this or that particular problem that it was really
only with the reconciUation of Mendelism with natural selection in
the last twenty-five years that biologists have begun thinking in broad
evolutionary terms.

ALL THINGS CONSIDERED ■ 269

Sutherland: What areas do you think it would be best to pursue
now — what seems the most rewarding line in each of your fields?

Veith: In my field, perhaps the most rewarding line would be to
find those moments or those evolutionary processes that will present
weaknesses, where maladaptation will occur, and where the mind will
not continue to function in its normal manner.

Huxley: I am sorry you wish to concentrate on maladaptation. I
should think it would be much better to concentrate on adaptation
from the positive angle.

Veith: But maladaptation has been studied much less.

Huxley: If I might jump over the fence into a field that is not my
own, I think that major progress will come in applying evolutionary
ideas to man, and doing so in the broadest terms — realizing that man
is an extremely peculiar organism, with the cumulative transmission
of experience as the basis for his evolution, and that, whether he wants
it or not, he is the agent for the whole future of this planet.

Adams: It is not enough to maintain our old disciphnary boundaries
— in my own case, to carry on a traditional kind of archeological re-
search — and merely to guide this with some new principles obtained
from wider fields. What is really called for is the bringing into play of
a whole series of disciplines, which can interact and can construct a
new, broadly synthetic approach that makes it possible to use these
ideas.

Huxley: That came out very clearly in the two ideas that to me
were the most important novelties in the whole Centennial. One was
MuUer's point that in the early stages of the development of modern
man — when he was really struggling with nature — natural selection
and social selection were synergistic and would have worked hand-in-
hand to encourage each other. IntelHgence would have been at a
premium, so we would have had genetic selection for better intelli-
gence, and this would have reacted on the social system. But as you
come to the great mass civilizations, the process probably works the
other way round and is dysgenic. The essential point scientifically is
that we can study interrelation of the purely biological and the social
components in psychosocial evolution.

The other point was the one Waddington threw into Panel Three:
the idea that man is equipped with some sort of built-in mechanism
for accepting what he is told when he is very young; he has to, be-
cause he is helpless as a baby and is not provided with a set of adap-
tive instincts. Of course, unquaHfied acceptance of authority has to
be corrected in later life through learning. When Waddington put this
idea to me in conversation before the panel, I said I was feeling just

270 ' ISSUES IN EVOLUTION

like my grandfather when he read Darwin's Origin of Species and said,
"How extremely stupid of me never to have thought of that." This is
a very fundamental point, which has to be worked out in all its im-
plications.

SOL TAX

THE CELEBRATION
A PERSONAL VIEW

When Charles Darwin and T. H. Huxley were members of the Royal
Anthropological Institute, scholars generally believed that human cul-
ture and society had evolved to their current states, leaving savages
! and barbarians as relics of bygone stages. But they also beheved that
i these primitive peoples could progress rapidly to the higher stages —
I especially with the help of Europeans. Neither fish nor fowl nor reptile
I could become mammahan, regardless of nurturing; but "Stone Age"
aborigines could become calico-wearing Christians. Differences among
peoples were considered evolutionary, in other words, but not "or-
ganic."

It is obvious that man, in many places, has passed through stages of
tribal hunting and village-tillage to achieve large societies with cities
and writing. Some surviving cultures remind us of obviously prehistoric
stages, but they are regarded as developmental varieties rather than as
living fossils. Not only is it now clear that all peoples known to us in
historic tunes are equally human, but the notion that different cultures
might be ranged on an evolutionary scale has also been largely aban-
doned. The differences among peoples are neither evolutionary nor
organic.

The complete separation in the twentieth century of man as an or-
ganism from man as a member of society and bearer of culture has
resolved the common confusion between race and culture. Hitler's dis-
astrous mythology was one culmination of a general belief that Euro-
peans are more effective than Asians or Africans as builders of civiliza-
tions, and Nordics are more so than Mediterraneans or Alpines. The
data of anthropology squarely contradicted the claims of the racists.
Cultural achievements of populations were shown to have cultural
causes, essentially independent of the genetics of the populations de-
veloping or carrying them. So culture and cultural history could be
treated apart from the organism, as both cultural historians (e.g., Fro-
benius) and evolutionists (e.g., Spencer) had long known. Culture,
the primarily human contribution to biology, is "superorganic" and
quite independent of "blood" or "race." A generation of students grew

271

272 ' ISSUES IN EVOLUTION

up convinced that biological and cultural anthropology needed each
other mainly to demonstrate the limitations of the biological in man.
Since the two branches were also specializing, becoming too extensive
together for any one scholar, cultural anthropology and physical an-
thropology have tended to draw apart from each other.

So we come to a science which proclaims itself "the study of man,"
yet views culture as though it were not part of man; which studies the
evolutionary process and traces the origin of man through the fossil
record, yet steadfastly separates man from all other animals; which
generally denies social and cultural evolution, yet uses the word "primi-
tive" — apologetically — for most of the living peoples and cultures it
studies.

This was the split personality of the science when, one evening in
1 955, 1 sat in the library of the Wenner-Gren Foundation in New York
City. It was a Friday evening "supper conference" at which William W.
Howells of Harvard was talking about physical anthropology. I was
there because I had other business in New York, because I like con-
ferences, and because I like anthropologists of all specializations. As
editor of the American Anthropologist, I had a good excuse to indulge
myself, but actually my thoughts had drifted away from Dr. Howells'
paper. He had mentioned Darwin's Origin of Species, which started me
musing. In another four years that book would be a hundred years old,
I remember thinking. Somebody would be organizing a celebration for
the occasion. Why should not anthropology be center stage? An ency-
clopedia nearby revealed that the exact date was November 24, a good
season in the academic world, since the school year is well underway
and the holidays have not yet begun.

My train of thought carried me home to Chicago. What institution
in this country was better suited to celebrate the centenary than the
University of Chicago, born ten years after Darwin's death, far away —
a celebration on behalf of the whole world? No personal interest;
purely intellectual and scientific. I promptly began writing letters and
talking to people: the president of the American Anthropological
Association (little knowing that I would be serving my own term as
president during the Centennial year!), the Dean, the Chancellor,
biologist friends, a widening circle of enthusiastic advisors.

But surely others must be having this idea, too, I thought. One way
to find out: Write to Julian Huxley and Sir Charles Darwin, telUng
them of our Celebration and inviting them to come. They might tell
us that they would be similarly involved in England, and we would
graciously give way and not compete. But again, they might not, and
we would have some sort of priority. Sir Charles, a renowned physicist,
stopped to visit us in Chicago the following March (on his way to Aus-
tralia) and asked in some puzzlement, "Why particularly the Univer-

THE CELEBRATION: A PERSONAL VIEW • 273

sity of Chicago?" When, in September, we met with Zoologist JuUan
Huxley (he was knighted in the next New Year's list) he did not need
to ask, being well acquainted with the historic pre-eminence of our
Department of Zoology.

The real mystery is why others did not pre-empt the opportunity of
celebrating the publication event of the century. In England celebra-
tions were planned, appropriately, for the 1958 Centenary of the read-
ing of the Darwin-Wallace papers before the Linnaean Society. The
centennial of Darwinism was, in fact, celebrated in many quarters, but
November 24, 1959 — the one-hundredth anniversary of publication of
Origin of Species — was left to the University of Chicago.
I Anyone who has organized or managed an event of these propor-
tions knows of the heart-breaking troubles we had over the years, the
mounting excitement as the machinery gets into motion, the obstacles,
satisfactions, and unforeseen frustrations encountered. Whether I
wanted to be Chairman of the Celebration Committee I cannot tell;
but nobody else would take on the job and I have never been able to
resist trouble. But I did not expect the sudden death through snakebite
of Karl Schmitt, who had been the perfect choice to invite and work
with the biological scientists; I did not anticipate that leukemia would
sap the strength and then take the life of Robert Redfield, who had
been my mentor in anthropology. When S. L. Washburn left the Uni-
versity, I was the only anthropologist left on our Committee, with
Alfred Emerson in zoology, Everett Olson in paleontology, Chauncy
Harris in geography, and Ilza Veith in history of medicine. Later
Zoologist Burr Steinbach joined the group.

As the papers began coming in and correspondence piled up, in-
I creasing demands were made of the Committee. As Chairman I was
heavily dependent on the others while sharing their responsibility. I did
not know the eminent zoologists, botanists, psychologists, physicians,
biochemists, and others who had been invited. I did not know their
work nor how it related to evolution. People assumed that I knew
much more than I did, and like a physician in a difficult case I had to
exude confidence while trying frantically to learn. I told myself that,
with so great a range of subject matter, nobody could be expected to be
omniscient, but when a subjective judgement had to be made, how I
hated my ignorance!

One of my most encouraging moments came when a knowledgeable
outsider, who had been reading the papers as they came in, told me
that he thought they were remarkably creative, the best such collection
he had ever seen. This changed things in some subtle way; the amateur
gardener who misreads all the directions and works so hard m igno-
rance that he sees nothing but the weeds is told by an old hand that
he has the best perennial garden in the neighborhood!

274 ■ ISSUES IN EVOLUTION

In reality this praise from our reader may have served most by eas-
ing my guilty conscience, for I was not putting as much time and
energy into the planning as I had originally intended. Partly by chance,
but largely by my own improvidence, I became involved in a number
of long-term projects during the years immediately preceding the Cen-
tennial. I was Chairman of the Department at the University; program
chanman for the 1957 American Anthropological Association meet-
ings held in Chicago; and (taking effect at that convention) President-
elect and then President of the Association. Perhaps most improbable
of all, I was at the same time engaged in founding the new journal
Current Anthropology. It was to have world-wide scope, keeping an-
thropologists everywhere informed of the latest advances; therefore, I
spent the first half of 1959, the Centennial year, on three journeys to
five continents to determine what the new journal must include. We
put the first issue of Current Anthropology in the mails on the very
eve of the Celebration.

Had the Darwin Centennial Celebration been a miserable failure, I
could have taken full blame. Since it all turned out so well, I must look
elsewhere to bestow credit. Clearly at least three sets of angels were
involved: (1) the Celebration Committee and the scientists they se-
lected; (2) the staff that handled the multiple details in blissful ig-
norance that they were doing the impossible; and (3) Charles Darwin
himself and the genuine importance of the concept of evolution. j

In choosing the participants, the Committee must have been extraor- I
dinarily wise. There were many good people we missed, but we made
almost no positive mistakes. Almost all the papers were first-rate, and
as each was distributed it seemed to inspire others. Or was it the oc-
casion that encouraged each to do an especially important piece of'
work? The quality of the participants must account for the response :
in advance to the Celebration — the response of foundations to our
requests for money; the response to invitations to come to Chicago for
the Celebration. The quality of the papers gave confidence to the par-
ticipants and to the Committee, so that many arrived early to devote as i
much as a week to preparing for the panel discussions. Sir Julian Hux- ■
ley and Alfred L. Kroeber had been in residence at the University dur-
ing the final quarter of 1959; along with Committee members and I
other participants, they had participated in seminar groups of faculty
and graduate students, aimed at proposing issues for discussion, from i
which the various panels might select their final agendas during their
pre-Celebration briefing sessions.

In retrospect it seems as though those panel discussions should have
terrified us, like dangerous and unpredictable firecrackers. Bring to-
gether highly individualistic scholars chosen for scientific ability, andl
give them problems for discussion that go beyond the specialties ini

THE CELEBRATION: A PERSONAL VIEW

275

which any of them feel comfortable. Let them group themselves
"blind" into panels, regardless of personahty; give them about thirty
hours to become acquainted, some having met for the first time. During
that period ask them to agree on topics for discussion, but not on the
answers, of course. Then put them on a stage, bright with klieg lights,
before large, eager audiences of critical people. By all rights, the fire-
cracker should have exploded in our faces, or, worse, simply fizzed out;
but panel after panel — day after day — the atmosphere remained elec-
tric, the discussion sparkled.

The Celebration was the Panel Discussions; the panels were partici-
pants; the participants were great scientists who did what no great
scientist should be expected to do. The Celebration was good because,
from beginning to end, the Committee and those they had chosen did
so well.

The remarkable staff that brought off the Celebration was fortu-
nately inexperienced in a project of such magnitude: hence we could
agree happily to do things that experienced people would have dis-
missed as impracticable. We started out by generously inviting the
whole world. Acutely aware of the limitations of our facilities, we
decided to protect ourselves by an elaborate advance registration sys-
tem, taking into account every event listed in the program. The num-
ber and variety of the events, plus the fact that some were free, some
paid, with special rates to certain groups, made for bookkeeping that
would have staggered imaginations which we fortunately did not have.

A resolution to the ticket problem was a universal ticket, covering
all events, a sample of which is shown here:

•si 2 >ii«
« I «g I ■§ 8

A I Ul ■• ^

.c !

2 2 »-<'^

•^ M ° *<> S

c 1 lu ^ ^

Film Preview

"The Ladder

of life"

Nov. 25
Mandel Hall
2:45 P.M.

PANEL I

Nov. 24

Mandel Hall

1:30 ?M.

PANEL II

Nov. 25
Mandel Hall
9:45 A.M.

PANEL III

Nov. 26
Mandel Hall
9:45 AM.

PANEL IV

Nov. 27
Mandel Hall
9:45 A.M.

University of Chicago Darwin Centennial Celebration

NOVEMBER 24 to 28, 1959
REGISTRATION AND TICKETS OF ADMISSION FOR:

(Name)

This ticket will admit the bearer to the events listed.
Admission to all events is by ticket only.
Seats will be reserved only until time shown.

Udara by
L. S. B. Leakey

Nov. 25

Mandel Hail

3:30 P.M.

Centennial Dinner

Nov. 24

Hutchinson Commons

6:00 P.M.

Program In Mandel Hall following

dinner: 8:30 P.M.

Thanksgiving

Dinner

Hutchinson
Commons
Nov. 26
6:00 P.M.

PANEL V

Nov. 28
Mandel Hall
9:45 A.M.

5 « < — < 2

? 5*2:9

(A

-? M
HfsZ

kzgOZ
OS?

^

276 ' ISSUES IN EVOLUTION

When it came to seating the 2,500 registrants, we were determined
to allot the 1,000 seats available in Mandel Hall, our largest audi-
torium, with due consideration for each individual. Each was to have a
seat in Mandel for two or three of the five panels, with seats elsewhere,
in halls with sound equipment, for the remaimng sessions. Each regis-

THE UNIVEPxSITY OF CHICAGO

DARV7IH CENTENNIAL CELEBRATION

Movember 2h-2o. 1959

To: Registrants

From: Sol Tax

In this envelope you sJiould find your tickets, program, name badge, and
booklet of abstracts of the papers prepared for the Darwin Centennial Celebration
discussions. Some of these items need explanation beyond that in the program.

Of nearly 3,000 who have wished to register, we have had to turn away one
third. Even so, our space and facilities are being over-taxed. To be fair to
all and to protect tine comfort and sanity of everybody concerned, we have had to
set up an elaborate prdceedure which (if it works) will be amusing to watch.

The problem is mainly with the five panel discussions. Leon Mandel Hall is
the only appropriate auditorium on campus and it holds only a thousand people,
(Prospective donors of a larger hall are referred to the Development Office)
Registrants have registered for different panels; but even so, from 1,700 to
1,000 want to get into each one.

I The large white ticket is your identification card. It is num-
j bered to correspond to the entry of your registration in our books.
I If you registered for more than one ticket and gave only one name,
; all your tickets have the same number. This ticket has on it all
the events except the musical show "Time Will Tell". If you did
not rej:.e3t tickets for an event, that event has been voided on
your ticket. Additional tickets for "Time Will Tell" are available
' at the Mandel Hall Box Office.

V/e wanted to be fair to everyone and we knew that not everyone would be equally
interested in every panel. Therefore we set up two auxiliary halls — Breasted
Lecture Hall in the Oriental Institute and the auditorium in Kent Hall -- where
the panels can be heard but not seen. We then went through our registrants and
seated each one individually according to his interests. \7e gave you a seat in
Handel Hall for those panels which we thought you were most interested in, a seat
in Breasted or Kent for panels of marginal Interest. This is marked on your
tickets in the following manner:

Mothing punched out = a seat in Mandel Hall

A ^ punched out = a seat in Breasted Hall

A. O punched out = a seat in Kent Hall

Scats In Mandel Hall will be held only until time shown on the ticket; THEM, any-
one holding a ticket marked for Breasted Hall (a ^ punch) will be allowed into
Mandel to fill the vacant seats. If you hold a ticket for Breasted Hall, you
should therefore join the stand-by line along the east wall of the Mandel cor-
ridor. If you don't get into Mandel, you will have 5 or 10 minutes to get to
Breasted where a seat will await you.

THE CELEBRATION: A PERSONAL VIEW • 277

trant's scholarly discipline, the distance he had traveled, the days he
would be attending, and so on were reviewed in deciding those panels
most likely to interest him. To attempt such individual seating in the
hurry and dash of last minute preparations was clearly ridiculous, but
again we did not realize this.

The scope of the registration problems and how the Celebration staff
dealt with them may be presented to the interested reader most graphi-
cally by reprinting here a copy of the instructions to registrants. An
air of amused appreciation pervaded the halls as the visitors went
through the complicated contents of the large manila envelope that
each was given.

Holders of seats in Handel must get tliere before the time shown on the
ticket or their seats will be taken by those from the stand-by line. If you hold
a seat in Handel and are late, there will be room for you in Breasted.

If you hold a seat in Kent Hall (a O punch), you cannot get into Mandel
no matter what; do not "stand-by" but go directly to Kent Hall.

i Centennial or Thanksgiving Dinner; j

j If you have a ticket for the dinner, stop at the "seating desk" j

in tlie Reynold's Club as soon as possible to reserve your place. V/e
! assume that friends will want to make up parties. Since there will'
I be no speeches in the dining hall, the location of your table Is not
I important.

Both dinners are sold out to capacity; but you may add your name
I to a waiting list at the seating desk in case of cancellations.

)

Tuesday Evening

On Tuesday evening the entire first floor (300 seats) of Mandel Hall is re-
served for those attending the Centennial Dinner. Any other ticket holders may
come to the program, to the limit of the balcony.

V/ednesday Afternoon

l«lote that your ticket is valid for the two V/ednesday afternoon events ~ the
lecture by Dr. Leakey and the film "The Ladder of Life". In each case only Man-
del Hall will be used, only registrants may attend, and first come, first served.
(Participants in the National Conference will have seats reserved for Dr. Leakey's
lecture because their conference keeps them from the film.)

Mame Badges

The name badges of special groups have been color coded as follows:

Buff for volunteer student workers

Blue for Participants and Darwin Centennial Committee members

Yellov; for the Society for tiie Study of Evolution

Red for The Institute for High School Biology Teachers

Salmon for the University of Chicago Faculty

Green for official delegates

278 • ISSUES IN EVOLUTION

Among the contents of the registrant's envelope was a 64-page book-
let of summaries of the Centennial papers. These 45 essays, written in
advance and exchanged among the participants, were not to be read at
the Celebration itself. To acquaint the audiences with the material,
and hence help them appreciate the discussions, it was decided to
summarize the papers in the form of a booklet. But who was to do the
abstracting? Charles Callender, the Conference Director, was a logical
choice, but he had been unable to begin the summaries until shortly
before the deadline. Alfred L. Kroeber took responsibility for all the
anthropological papers, and several others were done by a young biolo-
gist, David Ingle. A neighborhood letter service agreed to work day
and night to print the booklets before the Celebration and deliver them
to my home, where we were also working day and night. They actually
did the job, and delivered them as promised, but then someone dis-
covered that the pages were out of order so that they could not be fol-
lowed. A moment of panic, and then the solution, an errata sheet, as
follows:

ORDER OUT OF CHAOS:
or
Nine Pages That Shook the Editor

When you come to the end of Page 34, turn
to Page 39. Read through Page 43. Then turn
back to Page 35 and read through Page 38. Then

turn to Page 44 and you are out of the maze.

All through that last frantic weekend, we were printing tickets and
stuffing envelopes, with as many helpers as we could find. Registration
began Monday morning, and at 8 a.m. trucks came to the house to de-
liver the material to the registration room barely ahead of the crowds.

I have described only a small fraction of the work involved in pre-
paring for the Celebration. The lesson is that to do an ordinary job,
have experienced people who will follow proved routines and avoid
"fooHsh" things which would be good to do if they were practicable.
But if there is an extraordinary task to be done unprecedentedly well,
get creative, intelligent, and devoted people, wholly ignorant of all
pitfalls in the interesting paths they will choose.

Who were these people? In 1958, our Committee was struggling

'M-'^Jr*-.:

ON

THE ORIGIN OF SPECIES

BY MEANS OF NATURAL SELECTION,

PRESEKVATION OF FAVi»UKED 1?AC'ES IN THE STlUtWil.E
FOR LIFE.

By CHARLES DARWIX. M.A.

FELLOW OF THE KOVAL, CFMUicli: \i.. LtNNM.AN. 1,1,
AUTHOR OF » JdUKNAL OF iU^KAECIlES M'liLVf; Jj . M, ,. ,,, ,
KOINP TIIK WOftl.!).'

LONDOK:

JOHN MUEEAY, ALBEMARLE STREET.

1858,

'»« rigU of TramkUim in i-eterwd.

COMMITTEE

for the
DARWIN CENTENNIAL CELEBRATION

SOL TAX, Chairman, Department of Anthropology
ALFRED E. EMERSON, Department of Zoology
CHAUNCY D. HARRIS, Department of Geography
EVERETT C. OLSON, Department of Geology
H. BURR STEINB ACH, Department of Zoology
ILZA VEITH, Department of Medicine

CHARLES CALLENDER, Conference Director
MARIE-ANNE HONEYWELL, Conference Secretary
JEAN DAMES and ROSE WEINER, Assistants
ROCHELLE DUBNO W, Director of volunteer work by students
MARIANNA TAX, Assistant

INSTITUTE AND NATIONAL CONFERENCE
FOR HIGH SCHOOL BIOLOGY TEACHERS

RICHARD BOYAJIAN, University High School JOHN C. MAYFIELD, the College

Director of the Institute Director of the National Conference

Committee: G. ERNST GIESECKE and D. BOB GOWIN, Graduate School of Education;
BARBARA F. FALSER, Department of Botany; HEWSON H. SWIFT, Department of Zoology.

THE UNIVERSITY OF CHICAGO

■

DARWIN CENTENNIAL

1

CELEBRATION

NOVEMBER 24-28, 1959

Joining the Uniuersity in sponsoring the Darwin Centennial Celebration

are the National Science Foundation, the Wenner-Gren Foundation for Anthropological Research,

and the National Institutes of Health. The first two have contributed transportation and living expenses

for the participants; the third, costs of the panel discussions.

Sol Tax

TUESDAY

NOVEMBER 24

1:30 P.M.
MANDEL HALL

ISSUES IN EVOLUTION— "INTRODUCTION'
Sol Tax

2:00 P.M.
MANDEL HALL

ISSUES IN EVOLUTION— I: "THE ORIGIN OF LIFE'

Panel Discussion

Chairmen: Harlow Shapley and Hans Gaffron

SIR CHARLES GALTON DARWIN
TH. DOBZHANSKY
earl a. EVANS, JR.
G. F. GAUSE

RALPH W. GERARD

H. J. MULLER

C. LADD PROSSER

6: 00 P.M.

HUTCHINSON COMMONS AND COFFEE SHOP

CENTENNIAL DINNER
Presiding: Chauncy D. Harris,

Dean, Division of Social Sciences

The Citizens Board of the University of Chicago will join
the after-dinner program. Other registrants are
invited to the limit of seating capacity.

8:30 P.M.
MANDELHALL

WELCOME

Lawrence A. Kimpton, Chancellor, University of Chicago

"THE DARWIN CENTENNIAL CELEBRATION"
Sol Tax

"DARWIN THE TRAVELLER"
Sir Charles Galton Darwin

Sir Charles Darwin

Panel One

The audience in Mandel Hall

4 crowd at intermission

WEDNESDAY

NOVEMBER 25

9:45 A.M.
MANDEL HALL

ISSUES IN EVOLUTION— II: "THE EVOLUTION OF LIFE'

Panel Discussion

Chairmen: Sir Jullan Huxley and Alfred E. Emerson

DANIEL L AXELROD
TH. DOBZHANSKY
E. B. FORD
ERNST MAYR
A. J. NICHOLSON

EVERETT C. OLSON
C. LADD PROSSER
G. LEDYARD STEBBINS
SEW ALL WRIGHT

2:45 P.M.
MANDEL HALL

L. S. B. Leakey

"THE LADDER OF LIFE"

Advance showing of a film on "evolution in action"
Prepared by the Columbia Broadcasting System
for broadcast on CONQUEST November 29

3:30 P.M.

MANDEL HALL

Illustrated Lecture

"THE ORIGIN OF THE GENUS HOMO'

L. S. B. Leakey

EXHIBITS ON THE UNIVERSITY CAMPUS
REYNOLDS CLUB, SOUTH LOUNGE

University of Chicago Library Exhibit. The history of evolutionary theory and the influence of Dar-
win s writings on social thought and theology are shown in a book exhibit assembled by the Depart-
ment of Special CoUections of the University Library. Among the books on display from the Library's
coUections are first editions of seventeen of Darwin's works, including the Or.^in ofSpedes, presented
totheUniversitybyCol. William M.Spencer of Chicago. & J f - i'

University ofCalijornia at Los Angeles Exhrbit. A series of posters loaned by the University of Cali-
fornia at Los Angeles Biomedical Library illustrates Darwin's precursors, his life and work, and con-
^^L^:;!^^^^ '^''^—^ ^-^^°P— - genetics, embryology.

Panel Two

Sight-seers at exhibits

THURSDAY

NOVEMBER 26

9:45 A.M.
MANDEL HALL

ISSUES IN EVOLUTION— III: "MAN AS AN ORGANISM'

Panel Discussion

Chairmen: George Gaylord Simpson and F. Clark Howell

MARSTON bates

cesare emiliani

a. irving hallowell

L. S. B. LEAKEY
BERNH-ARD RENSCH
C. H. WADDINGTON

3:00 P.M.

ROCKEFELLER MEMORIAL CHAPEL

DARWIN CENTENNIAL CONVOCATION

Presiding: Lawrence A. Kimpton, Chancellor, University of Chicago

Convocation Address:

"THE EVOLUTIONARY VISION"

Sir Julian Huxley

Awarding of Honorary Degrees
Immediately following the recessional, official delegates will greet
the recipients of honorary degrees in Ida Noyes Hall.

6:00 p.m.

HUTCHINSON COMMONS

THANKSGIVING DINNER
Presiding: Edgar A. Anderson, President,
Society for the Study of Evolution

Sir Julian Huxley

8:30 P.M.
MANDEL HALL

A scene from ''Time Will TeW

"TIME WILL TELL"
An original musical play
written for the Celebration
by Robert A. Ashenhurst
and Robert Pollak

opening performance

[MILIANI

t i .1

Panel Three

G. G. Simpson, one of the recipients of an honorary degree

At the Convocation

FRIDAY

NOVEMBER 27

9:45 A.M.

MAN DEL HALL

ISSUES IN EVOLUTION— IV: "THE EVOLUTION OF THE MLf

Panel Discussion

Chairmen: Ralph W. Gerard and Ilza Veith

HENRY W. BROSIN
MACDONALD CRITCHLEY
W. HORSLEY GANTT

A. IRVING HALLOWELL
ERNEST HILGARD
SIR JULIAN HUXLEY

H. W. MAGOUN
ALEXANDER VON MURALT
N. TINBERGEN

i: 30 p.M.-4:30 p.m.
JUDDHALL126

INSTITUTE FOR HIGH SCHOOL BIOLOGY TEACHERS

The National Conference for High School Biology Teachers brings to this Institute
teachers from all over the United States. It is financed by a grant from the National
Science Foundation as a means of widening the influence of the Centennial Cele-
bration and of this Institute.

Panel and Discussion Sections
Chairman: H. Burr Steinbach

EDGAR ANDERSON

TH. DOBZHANSKY

H. J. MULLER

GEORGE GAYLORD SIMPSON

8:30 P.M.

mandel hall

"TIME WILL TELL'

SATURDAY

NOVEMBER 28

A scene from "Time Will Tell"

9:45 A.M.
MANDEL HALL

ISSUES IN EVOLUTION-V: "SOCIAL AND

CULTURAL EVOLUTION'

Panel Discussion

Chairmen: Clyde Kluckhohn and Alfred L. Kroeber

SIR JULIAN HUXLEY JULIAN H. STEWARD

H. J. MULLER LESLIE A. WHITE

FRED POLAK GORDON R. WILLEY

ROBERT M. ADAMS
EDGAR A. ANDERSON

Discussion at the teachers' institute

Panel Five

^^W o.TI

SATURDAY

NOVEMBER 28 (Conclusion)

12:00 M.
MANDEL HALL

ISSUES IN EVOLUTION— "CONCLUSION"
Sol Tax

1:30 P.M.-3 130 P.M.
JUDD HALL 126

INSTITUTE FOR HIGH SCHOOL BIOLOGY TEACHERS

Lecture and Film

EVOLUTIONARY ASPECTS OF SOCIAL COMMUNICATION IN ANIMALS

N. TiNBERGEN

Remarks

THE PLACE OF EVOLUTION IN THE CURRICULUM

Sir Julian Huxley

1:30 p.M.-5:3o P.M.

MANDELHALL

INSTITUTE ON SCIENCE AND THEOLOGY

Arranged with the cooperation of the Federated Theological Faculty

Lecfure

"CREATION AND CAUSALITY IN THE HISTORY OF CHRISTIAN THOUGHT"
Jaroslav Pelikan, Federated Theological Faculty
Lecture

"CREATION AND EVOLUTION IN PRESENT-DAY
ROMAN CATHOLIC THOUGHT"

The Reverend J. Franklin Ewing, S.J., Fordham University

Panel Discussion

"WARFARE OF SCIENCE WITH THEOLOGY"

C/w/;m,7/;; Jerald C. Brauer, Federated Theological Faculty

Harlow Shapley William O'Meara, Department of Philosod

Sir Charles Galton Darwin H. Burr Steinbach

C. H. Waddington Leo Strauss, Department of Political Science

8:30 P.M.

MANDEL HALL

"TIME WILL TELL"

Huxley addressing teachers

Jaroslov Pelikan

Panel at institute on science and theology

Father Ewing

tin 't

-'^^^^^I-

PARTICIPANTS

ROBERT M. ADAMS
University of Chicago

The Evolutionary Process in Early Civilizations

EDGAR ANDERSON
Missouri Botanical Garden

The Evolution of Domestication

D,\NIEL I. AXELROD
University of California, Los Angeles
The Evolution of Flowering Plants

MARSTON BATES
University of Michigan
Ecology and Evolution

FRANCOIS BORDES*
University of Bordeaux

Evolution in the Paleolithic Cultures

ROBERT J. BRAIDWOOD*

University of Chicago

Levels in Prehistory: A Model for the Consideration
of the Evidence

HENRY W. BROSIN
University of Pittsburgh

Evolution and Understanding Diseases of the Mind

MacDONALD critchley

National Hospital, London

The Evolution of Man's Capacity for Language

SIR CHARLES GALTON DARWIN

Can Man Control His Numbers?

TH. DOBZHANSKY
Columbia University

Evolution and Environment

ALFRED E. EMERSON
University of Chicago

The Evolution of Adaptation in Population Systems

CESARE EMILIANI
University of Miami

Dating Human Evolution

EARL A. EVANS, JR.
University of Chicago
Viruses and Evolution

PAUL FEJOS

Wenner-Gren Foundation for Anthropological
Research

Discussion Participant

E. B. FORD

University of Oxford
Evolution in Progress

HANS GAFFRON

Uhiversity of Chicago

The Origin of Life

W. HORSLEY GANTT
Johns Hopkins University
Pavlov and Darwin

G. F. CAUSE

U.S.S.R. Academy of Medical Sciences

RALPH W. GERARD
University of Michigan

Becoming: The Residue of Change

A. IRVING HALLOWELL
University of Pennsylvania

Self Society and Culture in Phylogenetic Perspective

CHAUNCY D. HARRIS
University of Chicago

Committee, Darwin Centennial Celebration

ERNEST HILGARD
Stanford University

Psychology after Darwin

F. CLARK HOWELL
University of Chicago

with S. L. Washburn

Human Evolution and Culture

SIR JULIAN HUXLEY

The Emergence of Darwinism

CLYDE KLUCKHOHN
Harvard University

Discussion Participant

ALFRED L. KROEBER
University of California, Berkeley
Evolution, History, and Culture

L. S. B. LEAKEY

Coryndon Memorial Museum, Nairobi, Kenya

* Unable to attend the Celebration.

H. W. MAGOUN

University of California, Los Angeles

Evolutionary Concepts oj Brain Function Following
Darwin and Spencer

ERNST MAYR
Harvard University

The Emergence of Evolutionary Novelties

H. J. MULLER

Indiana University

The Guidance of Human Evolution

ALEXANDER VON MURALT
University of Berne

A Decisive Step in Evolution: Saltatory Conduction

A. J. NICHOLSON

Australian Commonwealth Scientific and Industrial
Research Organization, Canberra

The Role of Population Dynamics in Natural

Selection

EVERETT C. OLSON

University of Chicago

Morphology, Paleontology, and Evolution

STUART PIGGOTT*

University of Edinburgh

Prehistory and Evolutionary Theory

FRED POLAK
University of Rotterdam

Discussion Participant

C. LADD PROSSER
University of Illinois

Comparative Physiology in Relation to Evolutionary

Theory

BERNARD RENSCH
University of Miinster
The Laws of Evolution

HARLOW SHAPLEY
Harvard University

On the Evidences of Inorganic Evolution

G. LEDYARD STEBBINS

University of CaUtornia, Davis

The Comparative Evolution of Genetic Systems

H. BURR STEINBACH
University of Chicago

Committee, Darwin Centennial Celebration

JULIAN H. STEWARD
University of Illinois

Evolutionary Principles and Social Types

SOL TAX

University of Chicago

Chairman, Darwin Centennial Celebration

N. TINBERGEN

University of Oxford

Behaviour, Systematics, and Natural Selections

ILZA VEITH
University of Chicago

Creation and Evolution in the Far Eiast

C. H. WADDINGTON

University of Edinburgh
Evolutionary Adaptation

SHERWOOD L. WASHBURN*
University of CaUfornia, Berkeley

with F. Clark Howell

Human Evolution and Culture

GORDON R. WILLEY
Harvard University

Historical Patterns and Evolution in Native New

World Cultures

LESLIE WHITE
University of Michigan

Four Stages in the Evolution of Minding

SEW ALL WRIGHT
University of Wisconsin

Physiological Genetics, Ecology of Populations and

Natural Selection

GEORGE GAYLORD SIMPSON
Harvard University
The History of Life

' Unable to attend the Celebration.

A scene during the television broadcast, "At Random" with
(left to right) Tax, Darwin, Huxley, Stevenson, Kupcinet,
and Shapley

THE CELEBRATION: A PERSONAL VIEW • 279

along without real staff, when the press and public began to take in-
terest and we all realized that "nothing was being done" about pub-
licity, invitations, the special convocation, the Celebration itself.
Charles Callender was a recent Ph.D. of our Department of Anthro-
pology with some experience in public relations. An excellent writer
and a careful scientist, he had never done administration; but we gave
him the title of Conference Director and he went to work.

In February of 1959 I returned from Asia for a two-month furlough
between conference trips for Current Anthropology. My assistant edi-
tor, Malcolm Collier (who had also helped in the first months of the
Darwin Committee), produced for me an applicant for a position as a
secretary who could keep straight my very tangled affairs. Marie-Anne
Honeywell is an M.A. in the humanities who was doing unchallenging
office work (while her husband gets his doctorate), and was happy to
see such a tangle. A granddaughter of a Nobel prize-winning chemist,
she has self-reliance born of confidence; skill and intelligence to match;
and the habits of a scholar-scientist to whom the jobs to be done over-
shadow the time of day, and the reward of solving a problem weighs
with a day's wage. Mrs. Honeywell, from February to September, was
fully occupied in helping me to manage the variety of my affairs; but
as the Centennial Celebration approached and the work snowballed,
she devoted more and more of her time to the chores of Conference
Secretary. She trained an office staff and eventually student helpers; she
found and bargained with printers and movers; she turned the mnu-
merable tricks that magically melt difficulties.

No matter how good our authors, how wise our Committee, or how
ingenious its Chairman, the Celebration could not have been accom-
plished without these two, so different yet so alike in their willingness
to plunge into the unknown and their ability to get out alive somehow,
if only at the last split second.

Charles Darwin and the genuine universal importance of the concept
of evolution might have foreordained the success of the Celebration no
matter what. Darwin proves to be more than a mere symbol; his Origin
of Species is a living classic in science. More than that, the concept of
evolution remains among the most significant and appealing ideas of
the intellectual world and a socio-religious issue as much as it was one
hundred years ago. When the thought of the Centennial first crossed
my mind, I evidently felt something about Darwin and evolution that
would have been difficult to demonstrate except through this fulfill-
ment- The Centennial was a success because it celebrated something
with deep meaning for the people of contemporary America. Evolution
is unfinished business for all kinds of people, and the names Darwin
and Huxley, with or without the prefix "Sir," call up still the variety of

280 ' ISSUES IN EVOLUTION

images they once did. One might have thought that with all the evi-
dence of a hundred years, science by now would have triumphed and
hostilities ended — particularly since science generally is so triumphant.
(Or is it precisely because science is so triumphant and threatens to
destroy us all that we rise to deny it where we can?) But Darwinian!
evolution also turns out to be one of the rare great tools for under-
standing ourselves and nature, and it was to this bright star that our
Celebration was hitched. In this old but vital context, every scholar and
every scientist had something to learn and something to give. And this,
more than anything we did, accounted for our success.

Whatever the Centennial did for others, for me it brought Darwin
and evolution back into anthropology. It forced me to see some of our
contradictions and helped me form some resolutions about the study
of man:

1 . Culture is part of the biology of man, of course, even though it is
passed on socially and not through the genes. It is a characteristic of
our species, as characteristic as the long neck is of the giraffe. The
general biological questions asked about the giraffe's neck are also
questions to be asked about the civilizations of man.

2. Culture is part of the evolution of man. Man is evolving con-
tinually as a species, perhaps more rapidly now than any other species.
Hence, processes of natural selection and the like are presumably
operative, but they are operative on the species, not on the particular
cultures of communities of men.

3. The term "evolution" is applied to both socially transmitted cul-
ture and gene transmitted biology because neither can establish an
exclusive claim. However, there is no identity between the two usages.
The cultural processes of continuity and change are different, and it is
only by analogy, if at all, that one can speak of "natural selection," for
example, in the development of cultures.

Culture must be studied as part of the evolution of man; but culture
change and growth must be studied in their own terms. Therefore,
anthropologists legitimately study culture apart from the organisms
who carry it.

4. Cultural behavior has a quality of arbitrariness, because it does
not flow through the genes and is therefore not anchored to the indi-
vidual. This is seen most clearly in the arbitrariness of the symbols in
language. Characteristically, therefore, cultures differ widely from
community to community; the communities of men have this quality in
common: each has its own special language, value systems, social
systems, etc.

5. The study of man becomes a comparative study of cultural differ-
ence within "genetic" sameness. The species is uniform, with what-

THE CELEBRATION: A PERSONAL VIEW • 281

ever individual differences there are in any population; but every com-
munity has its stamp. Both factors must be brought into the compari-
son,

6. Culture developed through time; archeology and common sense
both make it clear that culture developed from something rudimentary
in primitive australopithecines. Some stages are easy to unagine and
also marked in the evidence. By the time man became Homo sapiens,
he had behind him some unportant stages — tool-making, fire, speech,
and many other socially transmitted behaviors. These had developed
to the point where all men could live in the characteristic human com-
munity that we have known in history. Kalahari Bushmen and An-
damanese share with Londoners and Ukrainians the characteristic of
being parts of a self-conscious and ethnocentric community with its
distinct language, culture, social system, and convictions of right and
wrong. The latest such communities of Homo sapiens have the advan-
tage of much accumulated experience that the first lacked. It is fairly
easy to talk about "cultural evolution" with respect to science and
technology or community size and structure, things that are causally
related and for which there are archeological evidences. A theory of
cultural evolution implies regularities that go beyond archeological
evidence.

7. Only the "theories" of cultural evolution are in dispute. The cul-
tural anthropologists participating in the Centennial Celebration were
more committed to such theories than are many of their colleagues.
The general conclusion reached in Panel Five — that we now all believe
in cultural evolution — should be qualified: Some anthropologists will
accept only the evidences of records through time and believe that
these do not supply evidence of regular progression in social-reHgious-
aesthetic types accompanying the technological-economic stages where
these have occurred. However, all anthropologists recognize both the
general rise of culture from an almost non-existent form in animals to
the human stage, where culture seems to be everything. Beyond that,
they acknowledge the general progression in technology, shared differ-
entially, and in the size of the society. We are thus evolutionists for
the species, including its development of culture; but only some claim
the existence of regular progression in the whole of culture. Some of
these think of hunting and gathering tribes, or feudal states, as sur-
vivors of earfier stages living into the modern world; others are con-
cerned less with temporal succession than with processes of change
from one stage to another.

8. The terms "savage" and "barbarian" have been replaced by
"primitive" during the course of the century, to express the opposite
of "civilized." In any dictionary sense the meaning of "primitive"

282 ■ ISSUES IN EVOLUTION

makes it appropriate only for designating the first men, perhaps aus-
tralopithecines. It is, therefore, a doubtful courtesy to drop the nine-
teenth century derogatory terms and call most of the peoples of thei
world "primitive." It is ironic that the substitution is made most uni-
formly by those who have abandoned cultural evolution because theyv
deny that any culture can vaHdly be considered more advanced thani
any other!

So, for me, the Centennial brought Darwin and evolution back into
anthropology, not by resurrecting analogies, but by distinguishing mam
as a still-evolving species, characterized by the possession of cultures «
which change and grow non-genetically. Human evolution includes the
addition of culture to man's biology; "cultural evolution" at the human
level is quite a different matter. Anthropologists accept the first without
question; they are divided about the second.

INDEX

Abbevillian culture, 11, 99
Abelson, P. H., ffl, 77
Aberle, D. F., U, 346
Abortion, in Japan, III, 51
Abstract thinking. See Mind
Accidental synthesis, I, 66
Acclimation, I, 584-87
Acculturation, II, 361 and n., 385
Acheulean: culture, 11, 99, 105, 109; of
Levalloisian technique, II, 105, 148;
Middle, II, 102
Adams, Henry, 11, 407
Adams, Robert M., "The Evolutionary
Process in Early Civilizations," II,
153-68;

mentioned, H, 175; ffl, 223-30 passim,
241, 263-70 passim
Adaptation(s): co-ordinated, I, 399; cul-
tural, II, 324-25; III, 170; Darwin on,
I, 506; III, 209-10; in early human evo-
lution, III, 145; experiments in, I, 390-
402; III, 131; toward future function,
I, 341-42; origin of, I, 357-78, 381-
402; in population systems, I, 307-48;
principles of, I, 106-10; and selection,
I, 506, 510-11, 535, 587. See also Di-
rection in evolution
Adaptedness (random mutation plus se-
lection), I, 386-90
Adaptive: amplification. III, 72; changes,
I, 389-90; death, I, 327; definition of,
I, 542; monstrosities, I, 538-40; re-
sponses, n, 280-85; types in verte-
brates, I, 242; values, I, 541
Adaptive peak, I, 429-71 passim, 541
Adaptive radiation, I, 170-71, 237-43
Adena culture, 11, 121, 128
Aerobic conditions, I, 68, 70, 77, 78; ffl,

95-100
Aesthetics, possible beginning of, in birds,

III, 195
Africa. See Domestication; Evolution, hu-

man; Language; Primates; and specific

cultures, finds, and sites
Agassiz, Louis, I, 307
Aggression. See Behavior patterns
Agriculture: agrarian states, II, 180-82;

origin of, II, 67-83; patterns of, U,

72-73
Alchemy, stellar evolution as a higher,

1,34
Alexander, Frank, H, 358
Algae, I, 79, 143-45, 199-216, 219
AUee, W. C, I, 311, 313, 327, 551
Alleles, I, 429-71 passim
Allen, G., I, 58
Allen's rule, I, 109

AUometry: correlations between growth
of parts and of total body, I, 103-6;
phylogenetic rules of, I, 105
Alternation of generations, I, 207-17. See

also Reproduction
Altithermal climatic period, II, 119
Amadon, Dean, I, 370
American Anthropological Association,

II, 1 n.; Ill, 272
American Relief Administration, III, 180
Amery, L. S., II, 296
Amino acids: arrangement of, I, 60-61;
in, 85-86; heating of, I, 72; III, 95;
nature of, III, 137; proteins synthesized
from free. III, 83; spontaneous forma-
tion of, I, 72
Anaerobic. See Aerobic conditions
Anagenesis, III, 225
Anatolian Late Bronze Age, III, 90
Anders, Edward, ffl, 103, 104
Anderson, Edgar, "The Evolution of Do-
mestication," II, 67-84;
mentioned. III, 132, 207-43 passim
Andrews, E. C, III, 140
Andromeda triplet, I, 37
Angiosperms: alliance of, I, 231-35; an-
cestry of, I, 227-33, 237, 244; distribu-

283

284

INDEX

Angiosperms (continued)

tion of, I, 229-30, 233-38, 244-46,
255-57; evolution of, I, 157, 227-305
Angostura point, II, 118

Animal behavior: communication, 11,
353-56; HI, 179, 193-99, 215-17;
communication of learned habit, 11,
335-38; compared on conditioned re-
flex, in, 199; implications for man. III,
179-84 passim; insects, I, 319-21; lack
of symbolism in, II, 353-56; learning,
n, 260-62; social, H, 229-30, 309-71
passim; too use and invention, II,
296-97, 322-25; HI, 195-97, 231

Animal Behavior Farm (Cornell), II, 230

Anisomerism, I, 173

Anker, Herbert S., I, 72-73

Anthropocentrism, I, 25-31 passim; III,
57-59

Anthropology: Darwin's influence on, II,
5-11; early literature on, II, 10-11;
history of, II, 1-16 passim; resolutions
about, brought out by Centennial Cele-
bration (Tax), m, 280-82

Apes. See Primates

"Ape-men." See Australopithecinae

Aquinas, Thomas, III, 34

Arambourg, Prof., II, 27

Arataki, M., I, 105

Archeology: classification in, II, 155-57,
169-86; distortion in studies of. III,
221-23; interpretation of, II, 88; radio-
carbon dating in. III, 227; stage succes-
sion in, n, 154-59. See also Evolution,
cultural; Prehistory

Ariens-Kappers, C. U., II, 201

Aristogenesis, I, 404-5, 408

Aristotle, I, 34; II, 298; III, 35, 228

Arldt, Theodor, I, 279

Armstrong, E. A., I, 596

Arrhenius, G., II, 62

Arrhenius, Svante August, III, 104

Artificial insemination, II, 402-3, 449-55;
m, 59-60

Asch, S. E., II, 349

Atmosphere: early, I, 70; III, 76-77, 97;
Urey on, in, 78-79

Atoms: arrangement in molecules, I,
65-66; formation of, I, 35; questions
concerning, I, 24; unchanging, I, 34

Augustine, Saint, III, 23, 36, 228

Australopithecinae: cranial capacity in,
II, 38; ni, 166-67; culture in, n, 38-41;
dating of, HI, 163-65; dentition of, n,
22, 37-38; and human evolution, n,
23; in, 146, 159

Autecology: defined, I, 564; study of, I,

549
Autogenesis, I, 404-5, 408
Autokinesis, II, 235-36
Averroists, III, 35
Avery, Amos G., I, 592
Awareness: advances in organization of,

I, 17-20; evolutionary value of, in,

187-88; in Homo sapiens, U, 348
AxELROD, Daniel I., "The Evolution of

Flowering Plants," I, 227-305;

mentioned, I, 559; III, 107-43 passim
Azilian points, II, 105
Aztecs, II, 70, 71

Bacon, Francis, H, 207

Bacteria: and genetics, I, 56, 85, 88, 200,
201; purple, I, 77; and radiation, I, 200;
in, 90-91; reproduction of I, 88, 199-
217. See also Viruses

Baer, Karl Ernst von: embryogenesis, U,
207; rule of, I, 103; n, 190, 207; and
Spencer, II, 190

Bailey, V. A., I, 434

Baldwin, J. M., I, 15, 389

Bandelier, A. F., II, 164

Barbarism, I, 155; III, 281-82

Bartholomew, G. A., Jr., I, 564; II, 39,
322

Bates, Marston, "Ecology and Evolu-
tion," I, 547-68;
mentioned, IH, 145-74 passim

Bateson, William; anti-Darwinian leader,
I, 10; study on variation, II, 67;
mentioned, I, 350

Bauer, P. T., in, 240

Bayliss, Sir William Murdock, n, 224

Beach, Frank A., I, 596; II, 334, 335

Beals, Ralph, II, 175

Beard, J. S., Ill, 140

Beardsley, Richard K., n, 144, 174

Beckner, M., I, 525-30 passim

"Becoming," n, 255-67; UI, 178

Behavior: classifying, II, 385-86; III,
204; comparative. III, 183-86, 190-91;
of contemporary primates. III, 165-66;
Darwin on, in, 175, 179; data on, I,
599-610; II, 393-94, 400-404; and en-
vironment, n, 246-47, 403; evolution
of, n, 336-38, 359-62; III, 176,
187-92; experimental control of. III,
186; and form, II, 258-60; in func-
tional psychology, II, 282-85; mecha-
nisms of, I, 595-97, 601-5; methods of
study, n, 375, 397-400; m, 179, 180,

INDEX

285

182; motivation of, H, 374-75, 380-81;
III, 192, 194, 200-201; new patterns
from pre-existing elements, I, 172-74,
352-53; research in, 11, 376, 380,
395_97, 402; III, 190-91; and selection,
I, 602-5, 610; II, 403. See also Animal
behavior; Culture
Behavior patterns: abnormal, II, 373-422
passim; III, 179; aggressive, I, 10, 18;
III, 120-21; co-operative, 11, 353; emo-
tional, III, 192
— communicative: gestural, n, 330-31,
353-54; signs, III, 197-99; speech, H,
293-94, 300-302; symbols, 11, 249-50;
ni, 215-16; verbal. III, 179; trans-
mission of knowledge by. III, 197

— intellectual: learning, II, 260-62; III,
199; and mind, II, 373-85; III, 46-48;
pre-language, II, 298-300; scientific
study of. III, 179-84

—social: concept of, I, 319-21; HI, 171,
179; drives in, II, 229-30; early learn-
ing in. III, 392-403; group patterns, II,
329-38; and language, II, 295-98

—tool-using: II, 296-97, 322-25; m,
195-97, 231

Behaviorism, II, 271

Bellak, Leopold, U, 358

Benedict, Ruth, Patterns of Culture, U,
173

Benzer, S., I, 89; HI, 83

Beres, David, II, 358

Berg, L. S., I, 404

Bergman, G., I, 597

Bergmann's rule, I, 109

Bergson, Henri, I, 44, 50, 62

Bernal, J. D., II, 457

Bernard, Claude, II, 236

Bertalanffy, L. von, I, 528, 530

Bertani, G., I, 88

Bews, J. W., Ill, 140

Bias, in fossil record, I, 124-34

Bible: literary worth of, HI, 27-28; vo-
cabulary of. III, 31

Biocenosis, I, 563

Biochemistry: approach to origin of life,
I, 40; lability in, I, 588-90; and uni-
formity, I, 52; III, 182-83

Biogenetic rule, I, 103, 113

Biogeocenosis, I, 413

Biology: analytical nature of, I, 381; be-
fore Darwin, I, 118; favoring synthetic
theory of evolution, I, 405; foci of in-
terest in, I, 381; and history, I, 117-23

Biopoesis: biochemical reactions in, I, 54;
conditions for, I, 44, 77, 79; energy for.

I, 75; explanation of, I, 40, 52; and
limits of science, I, 44-50; HI, 91-92;
organic matter for, I, 68; on other
planets, I, 80-81. See also Life, origin
of

Biosphere. See Ecological units

Bipedahsm: development of, 11, 35-37;
selective value of, II, 46-47

Birds, I, 107-13, 157, 319, 387, 595-613
passim; III, 175-206 passim

Birdsell, J. B., I, 564; II, 9, 322

Birth control, n, 468-72; HI, 64

Bithorax phenotype, I, 394-99

Blair, F. W., I, 467, 607

Blest, A. D., I, 602

Bleuler, Manfred, H, 383

Blood groups, I, 194-95

Bloomfield, Leonard, U, 393; IH, 179,
194

Boaz, Franz, II, 159, 173

Bock, Walter, I, 373

Bodmer, Carl, II, 86

Bohr, Niels, II, 391; ID, 202

Boise, Charles, II, 25

Bondi, H., I, 32

BoRDES, Francois, "Evolution in the
Paleolithic Cultures," II, 99-110

Boreal element, I, 261, 263, 265

Boring, E. G., H, 282

Boucher de Perthes, II, 34

Bower, F. O., I, 231

Bowlby, J., II, 395, 396

Boyden, A. A., I, 525

Brachiation, IH, 152-54, 204

BRArowooD, Robert J., "Levels in Pre-
history: A Model for the Considera-
tion of the Evidence," 11, 143-51;
mentioned, H, 174, 175, 182

Brain: allometry in growth of, I, 104-6;
Broca's area in. III, 167; changes in,
II, 50; Darwin on, II, 33, 49, 187; III,
168, 171, 202, 205; evolution of. III,
145, 166-69; function, II, 187-209,
343-44; post-Darwinian concepts, II,
187, 188; quality of. III, 168; size and
capacity for adaptation, II, 324-25;
size and complexity, HI, 157; stem, II,
344; structural similarity of primate,
n, 343-44

Brandtner, F., H, 164, 165

"Breakthrough." See Transformations

Breuil, H., II, 355

Briflault, Robert, U, 13

Briggs, R., II, 453

Brooks, C. E. P., I, 563

Broom, Robert, II, 19

286

INDEX

Brosin, H. W., "Evolution and Under-
standing Diseases of the Mind," II,
373-422;
mentioned, III, 175-206 passim

Brough, J., I, 159-60

Bruce, J. Percy, HI, 7

Bruecke, Ernst, 11, 377

Briicker, E., II, 59, 162

Brues, Alice M., I, 468

Bryan, William Jennings, HI, 29, 30, 43

Buffon, Georges de, 11, 293

Burbidge, Margaret and Geoffrey, m,
101, 102

Biiri, Peter, I, 468

Burial, and fossil record, I, 125-29

Burnet, F. M., I, 85

Cain, A. J., I, 412

Callender, Charles, HI, 278-79

Calvert flora, I, 259

Calvin, John, HI, 36

Calvin, M., I, 74

Calvin, S., II, 58, 59

Cambrian land plants, I, 229

Campbell, Douglas Houghton, I, 279

Canalisation, I, 393-400, 587

Cancer: a biological phenomenon, I, 615
equivalents of, in bacteria, I, 620
equivalents of, in protozoa, I, 622-25,
equivalents of, in yeast and fungi, l,
618-20; nature of, I, 616-18; III, 98;
search for anticancer substances, I,
618, 624-27; theory of evolution and
study of, I, 615-16, 627

Cannon, W. B.: coined term homeostasis,
I, 315; emergency theory of, II, 276;
mentioned, 236, 275

Carbon: in chemical evolution, I, 67-77
passim; compounds, I, 570

Carbon dioxide: appearance in history of
earth, I, 70, 72; III, 97

Carbon-14: as biochemical tracer, I, 73-
dating method, n, 57-66 passim

Carboxyanhydrides, I, 72-73

Carpenter, C. R., II, 314, 317, 334; m,
166

Carpenter, J. R., I, 563

Castor, L., I, 617, 618

Catalysis, by unattached prosthetic group
I, 74 ^'

Catalytic proteins, spontaneous genera-
tion of, I, 63-64

Cathn, George, II, 86

Causal laws, I, 97-98. See also Laws

Cells: appearance of first, I, 50-53; chem-
ical mnovations at cellular level, I, 352;

composition of, I, 53; genetic altera-
tion in bacterial, I, 88; membrane
function in, I, 59; in, 98; mutations
in living. III, 81; reproduction of, I,
58; m, 85, 90

Cellular physiology, universality of, I, 53,
569-70

Cenozoic: environmental changes of, I,
237; flcristic changes, I, 272; vulcan-
ism and faulting, I, 255

Centennial. See Darwin Centennial Cele-
bration

Chance, B., I, 617, 618

Changes: accelerating rate of, 11, 256-58;
biological and cultural, shown by
hominines. III, 160; direction of, I,
541; III, 213-14; and epigenesis, II,
265-66; evolutionary, I, 349-80; III,
209, 224; of function, I, 361-67; mean-
ing of, II, 169; in neural evolution, II,
211-18 passim, 262-64; progressive,
in, 146; psychosocial. III, 197. ISee also
Direction in evolution; Mutation; Se-
lection

Chardin, Teilhard de, n, 28, 39, 253

Chase, M., I, 87, 102

Chatelperron point, 11, 99, 100

Chavin art style, II, 133

Chellean culture: implements, n, 27, 42;
in, 159; occupation horizons, II, 42;
stage of, II, 26, 27

Chelles-Acheul: hand-axe culture, U, 25,
43; tradition, II, 35

Chemical evolution, I, 67-79

Chemosynthetic bacteria, I, 204-5

Chetverikov, S. S., I, 409

Childe, V. Gordon, II, 89, 95, 149, 155,
156, 164, 172, 175; HI, 222, 225, 229,
230

China: art in, in, 14-15; concern with
evolution. III, 1, 2, 17; modern ad-
justments in. III, 15-16; Opium War,
ni, 15-16; philosophy of. III, 228;
speculation over creation, m, 3-4,
8-9, 181

Chlorophyll: in cell metabolism, HI, 78;
and enzymes, I, 50; and photosyn-
thesis, I, 53, 77; responsible for life
on earth, I, 50, 53; structural formula
of, I, 54

Christian thought on origins, HI, 29-40

Chromosomal cycles: in animals and
plants, I, 212-17; in fungi, I, 217-20.
See also Genes; Genetics

Chuang-Tzu, III, 6, 7

Civilizations: early, n, 154-164; growth
of, as evolutionary change, n, 165-68;

INDEX

287

"High," II, 176. See also specific en-
tries
Cladogenesis, in, 224, 225
Clark, Graham, II, 86
Clark, J. G. D., I, 564
Classification: archeological, 11, 155-57,
169-86; of behavior, II, 385-86; III,
204; by Cuvier, II, 8; of galaxies, I,
36; of glaciation, II, 59; UI, 161-62;
human systematics, III, 149; human
types (Pavlov), II, 225-26; of knowl-
edge, needed, II, 15-16; by Kroeber,
n, 171; by Linnaeus, II, 8; by Leslie
White, II, 172-76; of subhuman pri-
mates, ni, 145-63
Clausen, J., I, 468
Cleiodoic egg, I, 360
Clement of Alexandria, HI, 34
Clements, F. E., I, 562
Cleveland, L. R., I, 317
Climate: importance to plants, I, 234,
236-37; climatic selection. III, 122.
See also Environment
Clisby, K. H., H, 59
Clovis culture, H, 117-18
Cochise (Ariz, and N.M.): continuum
of cultures in, II, 119; populations of,
n, 130; sequence, H, 119, 120
Code system of nucleotide triplets, HI,

85-86
Coenzyme, I, 54-56
Colchic element, I, 262
Cole, F. J., I, 524
CoUias, N. E., H, 335
Collier, Donald, II, 175
Collingwood, R. G., H, 87, 92
Colombia, agronomists of, II, 69-70
Coloration: evolution of, and color vi-
sion, in, 192-93; as protection, I,
355-57, 556. See also Melanism
Communication: animal limitations in,
in, 179, 193-99; future of. III, 202-3;
gestural, II, 330-31, 353-54; symbols
in, n, 249-50, 293-94, 300-2; IH,
215-17; in transmission of knowledge,
ni, 197. See also Language; Speech;
Terminology
Communism: Communist Manifesto, HI,
29; forced labor under. III, 54; ide-
ology, ni, 255; view of eugenics, U,
428
Communities: competitive exclusion in,
I, 566; components of, I, 558-60; high
altitude, I, 565-66; stability of, I,
564-65; succession in, I, 566: th^nato-
cenosis and biocenosis in animal, I,
563

Comparative anatomy, H, 199; ni,

149-50
Comparative behavior, HI, 183-85,

190-91. See also Animal behavior
Comparative genetics, I, 197-226
Comparative method, I, 122-23
Comparative neurology, I, 211-18; III,

182-83
Comparative physiology, I, 569-94
Comparative psychology, II, 270-74
Comte, Auguste, II, 6, 204
Conditioned reflex: as basic learning, n,
200-204; cardiovascular, II, 232-34;
III, 199-200; Darwin's observations on
cardiac, II, 228-29; and environmental
limitations, II, 247-49; function, II,
230-32, 236-37; method of, in, 180
Condorcet, 11, 5, 6
Conduction. See Sa'tatory conduction
Confucianism, III, 14, 15, 228
Confucius, III, 2, 9
Conrad, G. M., I, 363
Consciousness: in animals. III, 187;
meaning of, in functional psychology,
II, 275, 281-82; "seat of," II, 344
Continuity of sciences, I, 46-50
Contraception: invention of, II, 469; oral,

HI, 51-53
Cope, E. D., I, 370; "law of the unspecial-
ized" by, I, 108; rule of successive in-
crease of body size, by. III, 151
Copernicus: Revolutions of the Heavenly

Bodies, ni, 29; theory of, I, 25

Correlations: between body size and size

of organs, I, 103-5; laws of, I, 19; in

structure and function of organs, I, 100

Cosmogony: Chinese concept of. III, 2-3;

terminology of, I, 33
Cosmos: characteristics of, I, 117; evolu-
tion of, I, 113; repulsion by, in gal-
axies, I, 37
Cott, H. B., I, 496
Coulborn, Rushton, II, 174
Council of Trent, III, 37
Council of Vienne, HI, 20
Craig, Dennis, I, 564
Crane, J., I, 596
Crawford, M. P., II, 353
Creation: balance between origmal and
continuing. III, 38-39; biblical stories
of, in, 31-33; concepts of, I, 32; II,
37; ni, 1, 3-4, 8-9, 30-40, 181; de-
fense of, in ancient world. III, 33-35;
definition of, and deism. III, 38; and
doctrine of evolution, II, 30; III, 30;
false idea of, HI, 252, 265; Gnostic
teaching of, HI, 35

288

INDEX

Creation of life. See Biopoesis; Life, ori-
gin of

Cretaceous: flora, I, 244-46; rocks, I, 228

Crick, F. H. C, I, 102

Critchley, Macdonald, "The Evolution
of Man's Capacity for Language," II,
289-308;
mentioned, in III, 175-206 passim

Cro-Magnon civilization, II, 303, 304,
379

Crop plants: cotton, II, 69; maize, 11,
69-70; miscellaneous, 11, 70-71, 78-79;
potatoes, II, 69; rye, II, 81-82; small
grains, II, 75-76; sugar cane, 11, 68;
wheat, II, 68

Cross-fertilization: Darwin studies on, I,
12-13; in genetical systems, I, 198

Crow, J. F., I, 448

Cullen, E., I, 603

Cultivation: native American, II, 114;
patterns of, II, 128-29. See also Do-
mestication

Culture: accumulative nature of. III, 208,
220-24; and behavior, HI, 280; and
behavior, by subhumans. III, 195-97;
characteristics of, 11, 314-16; HI,
171-73, 195, 207, 209-11, 216-17,
231-33, 271, 280-81; development of
human, II, 33-56, 111-12, 175-76; and
genetics, n, 442-45; HI, 146; and his-
tory, II, 10; m, 210, 230, 235-36;
microdynamic and macrodynamic ap-
proach, n, 16; negative feedback pro-
duced by advances in, m, 237; in New
World, n, 113-16, 134; from phylo-
genetic perspective, II, 309-71 passim;
and "race," confusion between, HI,
271; requirements for, II, 329; III, 167;
and "society" distinguished, II, 329;
survival of man through, II, 423-24;
transmission of, II, 321-22, 336-38;
present trend in studies on, II, 174-76.'
See also specific cultures; Evolution,
cultural; Life-patterns; Social structure

Cuvier, Baron, I, 153 and n.

Cytochromes, m, 98

Cytoplasmic inheritance, I, 533

Dakota flora, I, 244, 268

Daniel, G. E., II, 89

Darlington, C. D., I, 13

Darrow, Clarence, HI, 29, 30

Dart, Raymond, I, 564; n, 17 18 19

324; m, 158, 159
Darwin, Sir Charles GaIton, "Can

Man Control His Numbers?" II,
463-73;

mentioned, HI, 41-65 passim; 69-105
passim, 272
Darwin, Charles Robert: biographical
data, I, 1-21; II, 187; contributions, I,
1-2, 11, 385; and Freud, II, 195; a
"genius," as defined by Kroeber, I, 8-9;
and Haeckel, II, 204; and Lamarck, I,
114; III, 180-89; and Lyell and
Hooker, I, 5, 6; and Malthus, I, 5; ma-
terial available to him, II, 9; as medical
student in Edinburgh, I, 4; notebooks
on transmutation of species, I, 4; and
Pavlov, II, 193, 219-20, 237; and
Spencer, II, 195, 205-6, 269; student at
Down, England, 11, 207; visit to the
Galapagos, I, 9; and voyage on the
Beagle, I, 4, 9; II, 187, 207; and Wal-
lace, I, 6, 491, 519; III, 120; and Josiah
Wedgwood, I, 9; and Wilberforce, m,
43

character and personality: biologi-
cal humility, I, 26; capacity for general-
ization, I, 11; diffidence, I, 3, 4; in-
dustry, I, 2; neurotic symptoms, I, 3, 4;
passion for completeness, I, 3, 7; re-
luctance to publish, I, 3, 4, 6, 10; tena-
cious and comprehensive mind, I, 1 1
influence of: on Bateson and de
Vries, II, 67; on behavioral sciences,
m, 266; on biology, I, 10, 12, 118-19,
615; on breeding practices, I, 13; on
concept of human evolution, I, 17; II,
2, 309-11; m, 212; on doctrine of
original sin, HI, 30; on ecology and
ethology, I, 2; on psychology, 11,
269-80, 310; III, 59, 181, 188; on
theories of his own day, I, 382
opponents of: Bateson, I, 10; II, 67;
Mivart, I, 355, 365-66; nineteenth cen-
tury philosophers, II, 301-2; theologi-
cal, III, 24, 29-30

theories of: on abstract thinking in
animals, H, 299; on adaptation, IH,
209-10; on adaptive radiation, I, 161;
on bipedal locomotion, 11, 35; on car-
diac conditioned reflex, n, 228-29; on
competition, as main factor in selec-
tion, I, 496-97; III, 120-21; on cross-
fertilization, I, 12-13; on deposition
and erosion, I, 127; development of,
after publication of Origin, I, 10; on
distribution, I, 246-47; on divergence
of characters, I, 517; on domestica-
tion, n, 67; on early learning, n.

INDEX

289

229-30; on effect of "person," n, 229;
on emergence of novelties, I, 349; on
extinct species, I, 163; on the eye, ori-
gin of, I, 359; on family as primary
unit, II, 427; on the "fittest," I, 499,
505-6; on heredity, II, 277; on human
behavior, III, 179; on the human brain,
n, 49; on human evolution in Africa,
n, 17, 30; m, 159; inheritance of ac-
quired characteristics, 11, 221; on insect
groups, I, 309; on language and brain
size, II, 33; on man's lack of unique-
ness, in, 253; on man's mental capac-
ities, I, 11; II, 379; on moral sense, I,
13; n, 33, 308; of natural selection,

1, 11, 405; n, 158, 256; IH, 116; on
origin of new types, I, 13, 349; on
phylogeny of brain, mind, and behav-
ior, n, 187; on plant evolution, I, 227;
on plasticity in living organisms, 11,
236; on population, I, 506, 550; on pro-
gressive changes in organisms, I, 477;
on reasoning, 11, 309; on rock se-
quences, I, 127-29; on schizokinesis,
II, 227-28; on selection pressures, I, 4,
371; II, 33; on sexual reproduction and
selection, I, 333, 413; on teeth, re-
duced size of, n, 37; III, 156; of time,
in evolution, I, 11 ; HI, 60
writings: Autobiography, I, 161; 11,
205; Darwin-Wallace papers, HI,
62-63, 273; The Descent of Man, 11,

2, 10, 17, 49, 187, 204; The Expression
of the Emotions, I, 11; H, 187, 226,
230, 274; HI, 64, 186; Variation of
Animals and Plants, I, 96; II, 277; IH,
64. See also Origin of Species

Darwin, Mrs. Charles (Emma Wedg-
wood): concern over D.'s spiritual be-
liefs, I, 12; effect on husband's mental
health, I, 3; opposition to unorthodox
views, I, 4; and posthumous publica-
tion of Autobiography, I, 12

Darwin, Erasmus (grandfather of Charles
D.), I, 8; n, 91

Darwin, Francis (son of Charles D.), I, 12

Darwin, Robert (father of Charles D.),
autocratic with his children, I, 3, 4;
hostility to idea of evolution, I, 4; in-
fluence on son, I, 9; view of son's
abilities and character, I, 9

Darwin Centennial Celebration: anthro-
pological principles clarified by. III,
268, 280-82; impact of, on partici-
pants and lay public, 234, 246-48; IH,
263-64; lines of research suggested by.

m, 269; preparations for, ffl, 272-79;
purpose of, III, 249, 264-65; success
of, III, 279-80
Darwinism: defined by J. Huxley, I,
17-21; emergence of, I, 1-21; as in-
tellectual basis for Chinese upheaval,
m, 16-17; and organized religion, II,
1, 30; in, 30
Dating: by fossil record, I, 158; III,
163-65; human evolution, 11, 57-66;
III, 163-64; of plants, I, 293
Davis, D. Dwieht, I, 357, 524
Death of individuals, phylogeny of, I,

325-29, 560-61
DeBeer, G. R., II, 340-41; HI, 128
Deccan traps, I, 281
DeLaguna, Grace, II, 296
Delbruck, M., I, 410
Demerec, M., I, 410, 423
Dempster, E. R., I, 441
De nova origins, non-existent, I, 42,

173-74, 352-53
Dentition: in early primates. III, 155-56;

reduction in australopithecine stage, II,

37-38; significance of reduction, II,

47-48
Denzer, H., I, 105
Descartes, Rene, H, 206, 237, 454
Design, appearance of, in organic world,

I, 382-90. See also Direction in evolu-
tion
Development: effect of stress on, I,

398-99; hypothesis by Spencer, II, 207
de Vries, Hugo, Species and Varieties:

Their Origins by Mutations, 11, 67;

mentioned, I, 350, 409
Devolution, result of Chinese idea of, HI,

15
Dewey, John: on theories of emotion, II,

275-76; on transactional viewpoint in

perception, II, 282
Dialectic materialism, I, 41
Diastems, I, 128
Dice, L. R., I, 467
Differentiation: local, HI, 145; sequence

of, I, 105
Diffusion, as mode of evolution. III, 225
Diploid cycles, I, 125, 215, 217-18
Diploidy: and alternation of generations,

I, 207-17; establishment of, I, 215;

evolutionary significance, I, 125,

213-14; flexibility in, I, 216, 220-21
Direction in evolution (concepts and

theories) :

Adaptation toward future function, I,

341-42

290

INDEX

Direction in evolution (continued)
Adaptive peak, as "resolution of acting-
forces," I, 429-71

"Appearance of design in the organic
world," I, 382-90

"Biological adaptedness" (random mu-
tation plus natural selection), I, 386-90
"Dynamic homeostasis" (Emerson), I,
342

Evolutionary progress: summary of
concepts, I, 340-42

Experimental studies, I, 181-94, 390-
402

"Feedback," I, 338-40
"Inherent tendencies toward perfec-
tion" (vitalistic), I, 170, 171
Non-adaptive survivals and trends, I,
539

Origin of novelties, I, 357-78
Preadaptation, I, 364-67
Selectionist theory, I, 170-71
Teleonomy, I, 175, 341; m, 109
Transformation ("breakthroughs") to
new uses: in behavior, I, 173-74,
352-53; in function, I, 173-77; in struc-
ture, I, 172-75, 365
"Trends in the history of life," I,
166-72

"Universal goal is a posteriori at the
given moment and is simply survival,"
I, 175

Diseases: cause of, 11, 388-90; resistance
to, II, 389. See also Mental disorders

Disorientation, experiments in, HI, 186

Divergence, I, 12

Djetisbeds, n, 17

DNA: as carrier of genetic information,
m, 84; defined, HI, 82-86; essential
to life, m, 107; injections of, 11, 402-3;
mechanism of, HI, 143; model, HI, 74,
85-86; nitrogen bases for, HI, 74; of
proteins, HI, 115; in replication, m,
79, 82, 93, 108, 116; and RNA, in
cellular activity, HI, 85; and RNA dis-
tinguished, m, 84-85; schematic dia-
gram of, I, 61; size of molecule, m, 83;
in viruses, HI, 112

DoBZHANSKY, Theodosius, "Evolution
and Environment," I, 403-28;
mentioned, I, 95, 313, 314, 336 339
440, 446, 467; n. 111, 112, 256; m^
69-105 passim, 107-43 passim

Dohm, Anton, I, 360

Dollo's law, I, 173 n

Domestication: analysis by scientific
methods, 11, 67; earliest, n, 74-75;
hypotheses about plant, n, 71-73; im-

portance of minor crops to origin of,
II, 76; independent African center of,

II, 81-83; problems for investioation
in, n, 74-83; studies on plant, 11, 67-71

Dominance, genetic: among alleles, I,
437; emergence of, III, 110; factor in-
teraction in, I, 437-43

Dominance, social: and group succession,
I, 18; role differentiation as basis of,

III, 171, 178
Donaldson, H. H., I, 105
Doty, P., I, 66, 72

Doty polymerization, I, 73

Dougherty, Ellsworth C, I, 525; HI, 115

Drosophila, I, 15, 16, 182, 390-99,

413-24
Durkheim, fimile, II, 405
Dutch Institute for Brain Research, 11,

201

Earth, early conditions on, I, 67-79; III,
70

Earthquakes, epicenters of, I, 252

East, E. M., I, 440

Eastern Woodland, 11, 86, 123

Eccles, J. C, II, 235

Ecological units: communities, I, 551-52,
557-62; ecosystems, I, 556-57; eco-
tone, I, 551; individual as the basic, I,
548-50; paleoecology, I, 562; popula-
tions, I, 550-51

Ecology: balance of organisms in, I,
501-5; community structure in, I,
557-62; defined, I, 547; and evolution,
I, 547-68; as "outer-physiology," I,
549; population size as factor in, HI,
165; of primitive man, HI, 166. See
also Environment

Ectogenesis, I, 405

Eden points, 11, 118

Edinger, Ludwig, U, 188, 199-201

Edinger, Tilly, H, 199, 313

Efremov, I. A., I, 528

Eggan, Fred, H, 329

Ego: characteristic of Hominidae, II,
350-53; at different levels, m, 203; as
part of mental apparatus (Freud), 11,
196-99; in psychological maladjust-
ment, II, 358-59; and self-objectifica-
tion, n, 348-359

Einstein, Albert, I, 24; 11, 443, 454

Eiseley, Loren C, 11, 310

Elton, Charles, I, 560

Eltonian pyramid of numbers, I, 330

Emerson, Alfred E., "The Evolution
of Adaptation in Population Systems,"
I, 307-48;

INDEX

291

mentioned, II, 375; III, 107-43 pas-
sim; ni, 273

Emiliani, Cesare, "Dating Human Evo-
lution," II, 57-66;
mentioned. III, 145-74 passim

Emlen, John, III, 190

Emotion: classifying expressions of, II,
274-75; theories of, II, 275-77

Endemics: evolution of, I, 279-93; oc-
currences of fossil plants related to, I,
276; origin of areas of, I, 275-77

Energy, sources of, I, 75-77; III, 70, 74,
77, 93-95

Engels, Friedrich, 11, 91, 172

Entropy: increase in, I, 40; negative, I,
312

Environment: adaptation to, I, 406-8,
423, 505-11; balance between organ-
isms and, I, 501-5; changes in, I,
367-76, 584-87; III, 178; competition
in selection of, I, 492-96; and culture,
ni, 210; effect of behavior on, II, 403;
and evolution, I, 403-28, 409-26; free-
dom of, by man, I, 408; II, 247-49;
and heredity, I, 385; II, 278-80; labo-
ratory studies, I, 480-98; lav/s of in-
teraction with, I, 106-10; long-range
interaction with, I, 587-88; and muta-
tions, I, 399; operational, I, 554; per-
ceptual, I, 554; and populations, I, 333,
384-85; potential, I, 554; pressures
from. III, 145; response to, I, 408; III,
177; and selection, I, 405, 513-17. See
also Ecology; Selection

Enzymes: and anaerobic metabolism. III,
97; and arrangement of DNA mole-
cules, ni, 85-86; chemistry of, I,
61-63; and chlorophyll, I, 50; destruc-
tive, I, 65; in elimination of isomers,
III, 89; induction of, I, 384, 588-90;
precursors of. III, 87; for producing
nucleic acids. III, 70; reactions of, I,
71; ni, 86-87; in self-duplicating proc-
ess, I, 64

Eocene reef corals, I, 281

Ephrussi, B., I, 533, 619

Epigenesis, I, 265-66

Epigenetic: landscape, I, 393-401; proc-
esses, I, 399; m, 148

Epling, C, I, 468

Erlanger, J., II, 213, 214

Erosion: and deposition, I, 174; taxa in
regions of, I, 126-27

Eskimo culture, II, 122, 123

Ethical belief, cause of appearance of, in
man, III, 173

Ethnology, societies of, n, 10

Ethology: concept of. III, 183-84; evi-
dence from, II, 395-403; founded by
Darwin, III, 186; research in, 11,
380-81; III, 180-85

Eucaryota, 1,200, 217

Eugenics: through artificial insemination,
II, 402-3, 449-55; Communist view of,

II, 428; and population control, II,
463-73; questions to be considered in
regard to, II, 240-41; and selection, II,
430-35; III, 242-43

Evans, Earl A., Jr., "Viruses and Evolu-
tion," I, 85-93;
mentioned. III, 69-105 passim
Evans, H. J., I, 616; III, 74, 78, 83
Evolution: application of term, I, 23,
172, 310; II, 99; III, 102, 280; basic
definitions of Darwinian, I, 10-21; con-
ditioned reflex function in, II, 230-32;
creative, I, 425-26; developmental fac-
tors in. III, 146; direction of. III,
237-43; diversification in, I, 423, 425

III, 131; and environment, I, 409-28
gaps in knowledge about, III, 139-43
molecular basis for, I, 569; and mor-
phology, I, 524, 531-36; II, 107-8;
normal and linear, II, 104; and paleon-
tology, I, 537-43; parallel, I, 98, 170,
404, 425; paths in, I, 374-76; and
philology, II, 289-91; prospects and
goals of, I, 175-76, 542-43; II, 456-61;
regressive, I, 324-25, 336-38; and sex,

I, 413-17; 11, 384; III, 108, 113; socio-
psychological, II, 344-48; time dimen-
sion in. III, 141

cultural: beginnings of, II, 104-8;
III, 165-66; in China, III, 10-11; as
extension of organic concept, 11,
316-19; and genetics, II, 208, 424-30;
III, 146, 170, 209, 214, 217, 220-24; in
Mousterian stage, II, 109; in New
World, II, 136; of Paleolithic, II, 99,
102-3, 105-8; phyletic classification in,

II, 99-100; sequence of, II, 95; III,
209; theories of, II, 312; III, 281. See
also Culture; Evolution, Human

and genetics: co-enzymes and pro-
teins, I, 58; composition of popula-
tions, I, 407; determiners, I, 311; III,
120-21; gene frequencies, I, 435-37.
See also Evolution, organic; Genes;
Genetics

human: the brain in, II, 49-53, 187-
209 passim; III, 166-69; course of, II,
17-53 passim; in, 145, 166-74; dating,
II, 57-66; III, 163-64; differences
among peoples. III, 271; evidence of,

292

INDEX

Evolution {continued)

from comparative anatomy, HI,
149-50; goal of, I, 342; guidance of,
n, 423-73; in Pleistocene, II, 34-35,
64; short-term changes in, II, 469-70;
in speech, 11, 289-91, 306-8, 469-70;
time scale of. III, 161-65. See also
Culture; Evolution, cultural; Man
organic: adaptation in, I, 170-72,
311-12, 381, 387-88; HI, 72; in ani-
mals, I, 181, 308-11; III, 147-49; evi-
dence in fossils, III, 127-29; evidence
in structure and behavior. III, 129-37;
laws of, I, 95-116; models for the
study of, I, 529-30; novelties in, I,
349-80; in plants, I, 280-84; proc-
esses within and outside of organism,
I, 404-8; research. III, 107, 112-14;
theories of, I, 523-29. See also Adap-
tation; Evolution, theories of; Selec-
tion

psychosocial: future, n, 465; points
of agreement re. III, 265-66; in psy-
chiatry, II, 373-422; in psychology, II,
269-85, 314-16, 380; and somatic-
genetic, III, 246, 251. See also Cul-
ture; Evolution, cultural
AND religion: attitudinal changes, HI,
46, 253, 257; Catholic attitudes. III,
19-28; on creation and causality, HI.
29-40 ^

AND selection: chemical, m, 82; evi-
dence of, I, 467-68; isolation in, I,
462-67; multiple peaks and random
processes, I, 449-62; physiological
processes in, HI, 108, 123-25; theory
of, I, 530; III, 120-21. See also Natural
Selection; Selection

STUDY AND TEACHING OF: ancient Chi-
nese, III, 1,6-17; confirmation of Dar-
win by research, I, 95; current prob-
lems in, I, 353; II, 311-19; III, 4l_44,
207-8, 238; in education. III, 42; in-
tegration of facts since Orioin I
528-29; III, 251 ^ ' »

THEORIES of: Agassiz and Darwin I
307; before Darwin, I, 383; and can-
cer studies, I, 615-16; currem formu-
lation of, I, 10-21, 524, 528-30; in-
heritance of acquired characters, I,
383-88; and materialism, III, 24; math-
ematical framework, I, 429, 469-71-
Mendelian inheritance and selection l'
532; metaphysical, I, 527; models from'
various fields, I, 529-30; neo-Darwin-
lan n, 309-11; neo-Lamarckian, I,
527; paleontological, I, 537; psycho-

genesis, I, 97; saltation (mutation), I,
527-28; selection (synthetic), I, 171 n.
405, 523-27, 530, 531; III, 110; as
succession to higher levels. III, 112;
vitalist (perfectionist), I, 170-72; Wal-
lace and Darwin, III, 120-21
TRENDS in: fossil evidence of, I,
166-67; future, 197, 525-26; IH, 256-
257; general, I, 101; III, 146; long-
term, m, 137-39; present, I, 79,
106-10

EwiNG, J. Franklin, S.J., "Current Ro-
man Catholic Thought on Evolution,"
III, 19-28

Expansion: as adaptive radiation, I, 162;
of major groups, I, 154-59; of prime-
val life, I, 154-55; of marine life, I,
155, 156; primary and relaying, I, 156,
162

Experience: fixation of, 11, 256-57, 260;
role of individual in "becoming," III,
178

Exploitive system, man's advances in, HI,
148

Extinction: explanation of, I, 153 n., 163;
as fate of species, I, 153; frequency of,
ni, 141; prevalence of, I, 163; and re-
lay expansion, I, 162, 163

Extrapolations, two levels of danger in, I,
532-34

Eye, evolution of, I, 359

Faber, Ernst, lU, 7

Family-planning. See Birth control; Popu-
lation

Fano, U., I, 410

Far East, concepts of creation and evolu-
tion in. III, 1-17

Faron, L. C, n, 175

Farrar, F. W., II, 289

Feedback, I, 338-40; HI, 108, 125, 201,
214, 242

Fermi, Enrico, III, 248

Fermi Institute, III, 103

Fetalization, II, 342

Fischer, Emil, I, 59

Fisher, Charles, III, 186

Fisher, James, HI, 197

Fisher, R. A.: The Genetical Theory of
Natural Selection, III, 141;
mentioned, I, 15, 409, 433, 442, 468,
524, 529, 536, 547; HI, 139

Fiske, John, 11, 339, 340

Fitness, I, 198; HI, 124

Fleisch, H., II, 102

Fleming, R. H., I, 559

I

INDEX

293

Floras: Cretaceous, I, 228; evolution of
modern, I, 228-29; Tertiary, I, 246-47,
278; tropical and subtropical, I, 260
Flowering plants. See Angiosperms
Foerster, Werner, III, 31
Folsom type points, II, 118
Fontechevade remains, II, 64
Font-Robert points, II, 104, 106
Ford, E. B., "Evolution in Progress,"
I, 181-96;

mentioned, I, 467, 468; HI, 107-43
passim
Foreman, F., 11, 59

Fossil record: adaptive radiation in, I,
161-66; of African primates, 11, 17-56
passim, 305; bias in, I, 124-34; III, 128;
and burial, I, 126-29; change in num-
ber, I, 143-48; III, 128; comparison of
genera in, I, 142; completeness of, I,
125, 128, 129, 135-36; and concepts
in genetics, I, 537; HI, 127-28; dating
by, I, 158; III, 163-65; emphasis in
Darwin's day, I, 143; expansion and
equilibrium as processes revealed by, I,
154-59; exposure of, I, 131; extinction
common, 153, 161-66; of Homininae,
III, 159-66; of hominoids, HI, 151-59;
methods of collecting, I, 132; peculiar-
ities of, I, 144-46; Piltdown man, II,
313; preservation of, I, 125, 126-27;
problems of, I, 143-48, 538-40; sam-
pling of, I, 124-25, 128-34, 136-43;
study of, I, 537; trends in, I, 167;
values of, I, 528; variation in collec-
tions, I, 131-33
Founder principle, I, 184-88
Fox, S. W., I, 68, 72; HI, 95
Fraenkel-Conrat, H., I, 87
Franke, Otto, HI, 4
Frankfort, H., H, 88, 92, 96
Frazer, Sir J. G., H, 13, 311
Freedman, H. F., 11, 386
Freedman, L. Z., 11, 357
Freud, Anna: The Ego and the Mecha-
nisms of Defense, II, 358;
mentioned, 11, 396
Freud, Sigmund: on ego-instincts, 11, 384;
and Lamarck, II, 198; on mental ap-
paratus, II, 196-99; on practices of
mystics and psychoanalytic therapy, II,
198; work of, II, 195-99;
mentioned, II, 6, 13, 188, 377, 383,
389; m, 181, 186
— Writings: The Anatomy of the Mental
Personality, 11, 196; Aphasia, II, 196;
The Interpretation of Dreams, II, 378;
Project for a Scientific Psychology, 11,

196; The Psychopathology of Everyday

Life, n, 393; Three Essays on the

Theory of Sexuality, II, 377
Fried, M. H., II, 155, 156
Frobenius, Leo, III, 271
Fungi: asexuality in, I, 220; chromosomal

cycles in, I, 217-20

Gaffron, Hans, "The Origin of Life,"

I, 39-84;

mentioned. III, 69-105 passim
Galactocentrism, I, 26, 29-30
Galaxies: classification of, I, 36; Clouds

of Magellan, I, 36, 37; composition of,

I, 30; distance of, I, 29; expansion of,

I, 29; Milky Way, I, 28; progressive
evolution of, I, 29, 32, 36-37

Galileo, II, 7

Galton, Sir Francis: Hereditary Genius,

II, 277; Inquiries into Human Faculty,
II, 277; studies in human inheritance,

m, 182

Gamow, George, and the Primeval Atom
theory, I, 32

Gantt, W. Horsley, "Pavlov and Dar-
win," II, 219-38;
mentioned, HI, 175-206 passim

Garrod, Dorothy, H, 102, 144

Gause, G. F., "Darwinism, Microbiol-
ogy, and Cancer," I, 615-29;
mentioned. III, 69-105 passim

Geiger, Lazarus, II, 298

Geiringer, H., I, 430

Generalization (s): biases, I, 143; conclu-
sions from, I, 121; of evolutionary con-
cepts to other fields, II, 18

General Mills Research Laboratory, III,
94

Genes: and alleles, HI, 114-15; combina-
tions of, I, 95, 415; co-operation of
integrated, I, 206-7; differences in, II,
381-84; and distribution of human
blood groups, I, 468; equilibrium in, I,
314; equivalent to DNA, III, 74; errors
in self-reproduction of, I, 409-10; fre-
quencies in populations, I, 417, 430-38,
443_49, 457, 458, 459; molecular di-
mensions of, I, 89; mutation rates in
stable, I, 101; number of, I, 95; pur-
pose of, III, 126; recombination of, I,
315-16, 415-17; replacement of, I,
422-23; selective advantage of. III,
141; three-dimensional systems of, I,
430; and viruses, III, 69
Genesis, Book of, HI, 21, 23, 25, 29, 31,

33
Genetic assimilation, I, 15, 316-17

294

INDEX

Genetics: benefits from past cultural evo-
lution, n, 424-26; constancy in living
systems, I, 99; of continental popula-
tions, I, 422; and culture, II, 442-45;
m, 146; diploidy in, I, 218-19; drift,
I, 417-22; and homeostasis, I, 314; in-
adequacies of, for cultural evolution,
n, 426-30; inertia in, I, 314; mecha-
nisms of, I, 85, 334; and population,
I, 313-14; properties, I, 90; recombina-
tion, I, 197-207, 221-23; replication
and change in material in. III, 119; re-
search sequences in, I, 151-52; struc-
ture, and negative feedbnck in, HI,
237; svstems, I, 198-201, 220-21, 339,
423; m, 147, 149; techniques, II,
447-52; transduction, in contrast to
sexual reproduction, I, 316; in study
of evolution, I, 182, 532; variability in
population, I, 314, 390-98; III, 108,
114-16

Genetics, I, 524

Genotypes, I, 15, 349, 413-15, 456, 458

Geocentrism, and heliocentrism, I, 25

Geochemistry: in biopoesis, I, 77; work
of, I, 69

Geofloras: Antarcto-Tertiary, I, 270-73,
289, 290; Arcto-Tertiary, I, 229,
261-69, 274, 288, 290; area occupied
by, I, 246; centers of radiation in, I,
245-46; distribution of, in Early Ter-
tiary, I, 248; Madro-Tertiarv, migra-
tion of, I, 274-77. 290; Mediterrano-
Tertiary, I, 274; Neotropical-Tertiary,
I, 247, 258-60, 274; Paleotropical-
Tertiary, I, 247, 257-59, 261; plants
of modern aspect in Tertiary, I, 246;
Semiarid-Tertiary, I, 273-74; Temper-
ate Arcto-Tertiary, summary of, I,
269-70; Temperate-Tertiary, shifting
of, I, 260-66, 274; Tropical, I, 249;
Tropical-Tertiary, I, 247-57, 274

Geologic: evidence of evolution of plants,
I, 227-305 passim: evidence of plant
migration, I, 256; time, I, 166

Gerard, Ralph W., "Becoming: The
Residue of Change," II, 255-67;
mentioned, HI, 69-105 passiin, 175_
206 passim

Geren, Betty, 11, 215

Germs in space, HI, 70, 103-5

Gibbs, Willard, II, 443

Gierer, A., I, 87

Gillespie, Charles B., HI, 188

Gillispie, Charles Coulston, HI, 39

Glaciation: classifications of, II, 59; in
dating human evolution, 11, 44^45,

59-60, 63-65; HI, 161; effect on agri-
culture, m, 227; effects of Pleistocene,
III, 145; Gunz, II, 63; Inter-^lacials, 11,
64, 102; m, 164; lowan stage. II, 59
Last European, II, 44; Mindel, III, 164
peaks in. III, 165; Riss, II. 63; III, 164,
stages of. in, 161-62; Wisconsin, II,
59, 60, 117; Wurm, II, 59, 60, 63
Glass, Bentley, I, 468

Gloger's rule, I, 109

Gno'sticism, HI, 228

God: and the Bible, III, 21; denied by J.
Huxley, III, 46; evolution of m?n to-
ward, III, 28; as source of truth, in,
20; image of, in man vs. evolutionary
descent, m, 29;
mentioned, II, 1; in, 32, 37, 67

Goethe, P., I, 597

Goethe, Johann Wolfgang von, I, 41, 43,
119, 172 n.; n, 195. 199; III, 194

Goldhamer, H., n, 400

Goldman, Irving, II, 175, 176, 182

Goldschmidt, R., I, 192, 364, 373, 374,
467, 524, 528

Grains: Asiatic amaranths, II, 70; field-
sample study of small, n, 75

Granick, S., I, 352

Graptoiites, I, 155 n.

Grassl, C. O., II, 68

Graves, Robert, II, 13

Gravette point, n, 104. 105

Gray, Asa, I, 227, 247; m, 63

Greenberg, Joseph H., II, 182

Greenstein, J. P., I, 618: III, 102

Gregory, J. W., I, 279, 363

Gregory, W. K., I, 178

Grimaldi man, n, 304

Groningen Laboratory, II, 60

Groups: stabilization of, I, 18; survival
values of, I, 313. See also Ecological
units

Gulick, A., I, 279

Guppy, H. B., I, 279

Haag, W. A., n, 182

Haartman, L. von, I, 603

Hadal waters, and deposits, I, 129

Haeckel, Ernst, I, 549; n, 2, 199, 204;

m, 124

Haldane, J. B. S., I, 409, 433, 443, 466,
511, 524; ni, 76, 265

Hall, G. Stanley, II, 275

Hallowell, a. Irving: "Self, Society,
and Culture in Phylogenetic Perspec-
tive," II, 309-71;

mentioned, n, 177, 182; ni, 175-206
passim

INDEX

295

Hanike, E. A., U, 223, 224
Han Yu, HI, 10, 13
Haploidy, I, 208, 214, 216-17
Harada, K., I, 68
Harde, K. W., I, 105
Hardy, G. H., I, 413, 430, 559
Harlan, Jack, H, 76
Harlow, Harry, HI, 169, 190-91
Harris, Chauncy, HI, 273
Harrison, B. J., I, 330
Harrison, Jane, 11, 13
Hartland, E. S., II, 13
Hartmann, Heinz, II, 350; III, 203
Harvey, William, II, 230
Hawkes, Christopher, II, 86, 87
Hawkes, J. G., II, 69
Hayek, F. A., II, 388
Hayes, Cathy, II, 353-4, 356 and n.
Healinf, its basis in China, HI, 15
Hebb, D. O., II, 317, 352; III, 186
Hegel, George Wilhelm, I, 50
Heidelberg man, II, 99
Heim, Karl, III, 39
Heinroth, Oskar, II, 229-30
Heisenberg, W., H, 391
Heiser, C. B., Jr., II, 70
Heliocentrism, I, 25, 26
Helmholtz, Hermann Ludwig von, 11, 211
Hemin, I, 78

Hemoglobin, in plants, I, 55
Henderson, L. J.: The Fitness of the En-
vironment, in, 183;
mentioned, I, 556
Hennig, E., I, 107
Henslow, John S., I, 9
Heptarchy, seven Kingdoms of the, HI,

256
Herbaria, European, II, 74
Herder, Johann von. Origin of Language,

n, 299
Heredity: changes in, I, 384-85; char-
acter in, I, 15; concept of, I, 57; and
environment, H, 278-80; Galton
studies on. III, 182; ignorance of, in
nineteenth century, I, 14, 16; Men-
delian laws of, 11, 465; "nature-
nurture" controversy, II, 277-80,
466-68. See also Changes; Genes; Ge-
netics
Herrick, C. J., H, 201, 203, 204
Herrick, C. L., II, 201-4
Herriott, R. M., I, 86
Hershey, A. D., I, 87, 102
Heslop-Harrison, J. W., I, 387
Hess, B., I, 618
Hess, Eckhard, II, 395; HI, 195
Heteromorphic life-cycles, I, 210

Heterosis, I, 13

Heterozygous advantages, I, 190-91,
194-95

HiLGARD, Ernest, "Psychology after Dar-
win," n, 269-87
mentioned, HI, 175-206 passim

Hinde, R. A., I, 596; III, 197

Hino, S., I, 619

Hippocrates, II, 226, 230, 394, 404

Historiography, II, 1-16 passim; HI, 236

History: of life, I, 117-80; nature of, I,
117-19, 121-23; uses of, I, 120-21

Hitler, Adolf, III, 240, 271

Hockett, C. F., H, 320

Hoffman, W. C, D, 233

Hohokam culture, II, 127

Holland, J. J., I, 86

Holometabolous insects, adaptations in,
I, 16

Homogenesis, I, 404. See also Autogene-
sis

Homeostasis: dynamic, I, 342; functions
of, I, 314-15; increase in, I, 337-38,
341-42; and integration, I, 335-38; and
principles of schizokinesis and auto-
kinesis, II, 236; universality of. III,
123
Hominids, H, 17-53 passim; III, 145, 149
Hominines, HI, 159-60
Hominoids, early, II, 30; ID, 145, 149,

151-59
Homoiothermous species, loss of heat m,

I, 106

Homologous theory, I, 211-212

Homo sapiens, III, 166-74. See also Evo-
lution, human; Man

Honeywell, Marie-Anne, HI, 279

Hooker, John Dalton: and Darwin, I, 4,
5, 6; on forest in Antarctica, I, 270;
on insular floras, I, 278; mentioned, I,
9, 205, 227, 247, 279, 283, 288, 292

Hopewellian cultures, II, 121, 133

Hopkins, Sir Frederick G., I, 50

Hopwood, A. T., n, 18, 21

Hormones, I, 53-54

Hotchkiss, R. D., I, 88

Hovanitz, W., I, 468

Howell, F. Clark, "Human Evolution
and Culture" (with S. L. Washburn),
n, 33-56;
mentioned, IH, 145-74 passim

Howells, W. W., n, 328; ffl, 272

Hoyle, F., I, 32, 403

Huemac, identity of Quetzalcoatl with,
II, 162

Hughes, D. T., I, 616

Humanists, I, 42

296

INDEX

Humboldt, Alexander von, I, 41, 42-43,

46-47
Humboldt current, I, 285
Humboldt phase levels, II, 119
Hunting, big-game: and collecting pat-
terns, II, 123-24, 129; subsistence type,

n, 113

Hurzeler, J., HI, 155

Hutchinson, G. E., I, 334, 560, 564, 565
Hutchinson, J. B., 11, 69
Hutton, James, I, 118
Huxley, Aldous, Brave New World and
Brave New World Revisited, II, 392
Huxley, Sir Julian: "The Emergence of
Darwinism," I, 1-21; "The Evolution-
ary Vision," m, 249-61;
appearances and remarks of, at Cen-
tennial Celebration, III, 41-65 passim,
107-143 passim, 175-243 passim,
263-70 passim; on bacteria, I, 85; on
behavior, n, 386; Biological Aspects
of Cancer, I, 615; on biological evo-
lution, m, 224; on cancer, I, 615; on
cultural evolution, 11, 170; HI, 211,
219, 220; on children, n, 407; Evolu-
tion: The Modern Synthesis, HI, 112,
127; on extinction, I, 153 n.; on future
of psychosocial evolution, II, 465; on
genetic discontinuity, II, 2; on goal of
human evolution, I, 342; on influence
of Darwin, II, 375; on origin of adap-
tations, I, 357; on natural selection, I,
515, 524; HI, 116; on nervous system,
n, 215; m, 205; on work in the in-
dividual, m, 115

Huxley, Thomas Henry: Chinese accept-
ance of, m, 16-17; and concept of
comparative anatomy, n, 199; on con-
sequential characters, HI, 108; on crea-
tion, III, 30; on evolution and Chris-
tian doctrine, I, 40, 41; HI, 29; on evo-
lution as materialism. III, 24; on
Lamarck, I, 14; as supporter of Dar-
win, I, 9; n, 2; IH, 41

Hybrid corn, I, 13

Hydrogen: in anaerobic era, I, 78; loss
of, I, 69; transmutation in stars, I, 34

Hydrogen bomb. III, 49

Hyperadaptation, I, 519

Ice Age: elimination of exotic species, I,
262; mammals of, 11, 117

Id: in mental apparatus, n, 196-99; re-
pression of, ni, 172

Idealism, as force in America, m, 233

Ihering, Hermann von, I, 279

Imagination: in cave art, n, 355-56; in

China, EH, 3; in scientific work, I, 5
Imanishi, Kinji, 11, 335; III, 197
Immanent, the, and the configurational

I, 118

Imprinting, H, 229-30, 262; HI, 184
Inanimate bodies, relationships between

II, 240

Inbreeding, and cross-breeding, HI, 118
Incipient structures, selective value of, I,

365-67
India, HI, 49-53, 242
Individual: concept of the, I, 549; dif-
ferences, n, 277-80; integration, I, 307
Individuality, II, 385-88; HI, 115
Indo-European language origins, n, 8-9
Industrialization, world problem of. III,

50-53
Industrial melanism, I, 181-96 passim,

386-87
Indus Valley civilization, 11, 86
Inference, validation of, I, 121
Ingle, David, HI, 278
Inheritance of acquired characters: basic
concepts of, I, 383-84; Darwin on,
118, 119 and n.; II, 221; and genetic
assimilation, I, 14; and genetic value
of culture, II, 424-26; Pavlov on, II,
221-24; recent evidence of, I, 385-87.
See also Lamarck; Lysenko
Inorganic evolution, I, 23-84 passim, 117
Insect: origins, I, 108; IH, 134; popula-
tions, I, 321; societies, and human, I,
319-20
Insight, and comprehension, 11, 247
Instinct: and behavior patterns, II, 395-
403; concepts of, II, 272-74; III,
191-92; human. III, 174; motivation
and maturation in, n, 273-74
Institute of Microbiology ("Soviet), HI,

103
Insular endemics, I, 275-93
Insular floras: Darwin's on, I, 278; evolu-
tion of, I, 280-86; Hooker on, I, 278;
migration of, I, 278-79; origin of, I,
277-79; remarks on, in Origin, I, 278;
summary of, I, 292-93
Intermittent drift, I, 184-88
Intracellular synthesis, of virus, I, 87
Irmscher, E., I, 279
Iron, in mutation of atoms, I, 35
Iron metabolism, I, 352
Iron-porphyrin, I, 54
Irreversibility, laws of, HI, 151
Islands, types of, I, 282-84
Isles of Scilly, research in, I, 184-85
Isoalleles, study of, HI, 119
Isolation: mechanisms of, I, 181-96 pas-

INDEX

297

sim; ni, 132-34, 142; in diversifica-
tion, in, 109; physiological factors in,

ni, 133

Ivanitskaia, L, P., I, 621

Jackson, C. M., I, 105

Jackson, John Hughlings, II, 188, 189-92,
195, 196; HI, 181

Jain religion, III, 228

James, William, H, 275, 276

Japanese Monkey Center, II, 335; III, 171

Java man, II, 42, 45, 46

Jefferson, Thomas, on extinction of spe-
cies, I, 153 and n.

Jenkin, Fleeming, I, 14

Jennings, H. S., HI, 171

Jensen, J., I, 78

Jepsen, Glen, I, 524

Jespersen, Otto, H, 290

Jodrell Bank, II, 87

Johnson, M. L., I, 53

Johnson, M. W., I, 559

Jones, Ernest, II, 377

Jones, Sir William, H, 8-9

Jordan, Karl, I, 550

Judaism, lU, 33, 228

Judeo-Christian religions: ambiguity of
term creation in. III, 30; supernatural
elements in. III, 1

Jupiter, conditions on, HI, 97

Jurassic: climate, I, 236; plants, I, 228,
237

Kabuh beds, II, 40, 42, 49

Kafuan culture, II, 25

Kali, III, 255

Kallmann, F. J., II, 382, 399, 400

Kant, Immanuel, I, 41, 42; 11, 7

Kato, Genichi, II, 213

Kaufmann, L., I, 105

Keith, Sir Arthur, II, 304, 313; IH, 153

Kempthome, O., I, 529

Kendeigh, S. Charles, I, 319

Kepler, Johannes, II, 7

Kerr, W. E., I, 468

Kettlewell, H. B. D., I, 193-95, 387, 399;

m, 113

Kihara, H., H, 68

Kimura, M., I, 448, 449, 460, 462, 529

King, T. J., n, 453

Kleitman, Nathaniel, II, 222

Klemm, Gustav, II, 10, 12

Klomp, H., I, 596

Kluckhohn, Clyde (Chairman, Panel
Five), III, 207-43 passim
mentioned, 11, 112, 182, 326

Kochetkova, G. V., I, 620, 624, 625

Kohler, Wolfgang, H, 384; HI, 195

Kome flora of Greenland, I, 244

Kornberg, A., Ill, 83, 93

Korzybski, Alfred, II, 301

Kozloff, L. M., I, 86

Kroeber, a. L., "Evolution, History, and
Culture," II, 1-16;

mentioned, I, 8; II, 170-72 passim,
316, 347; IH, 207-43 passim, llS

Kruger, W., I, 105

Krumschmidt, E., I, 105

Kullenberg, B., II, 60

Kupcinet, Irv, III, 41-65 passim

Kurten, B., I, 160

Kusnezov, N. N., I, 425

Laboratory study of populations, I,

480-98
Lack, David, I, 500
Ladd, H. S., I, 563

Lamarck, Jean Baptiste: and Darwin, I,
118-19 and 119 n.; II, 221; IH, 188-89;
emphasized organism as major varia-
ble, II, 256; errors in, I, 14, 119; on
evolution of sexuality, I, 317; on ex-
tinction of species, I, 153 and n.; Freud
on, n, 198; Huxley, T. H., on, I, 14-15;
theory of, in two parts, I, 383-84;
mentioned, I, 309, 383, 547

Lamarckism, I, 350, 371, 412; II, 6; Neo-
Lamarckism, 118-19, 119 n.

Lamotte, M., I, 468

Lang, Andrew, II, 13

Langenheim, J. H., I, 554

Language: and altruism, II, 308; ana-
tomical basis for, H, 291-93; of Eu-
rope, II, 8-9, 72; evolution of, II,
51-52, 306-8; human capacity for, II,
289-308; Indo-European, II, 8-9; III,
212; intellectual behavior in, II, 298-
300; origin of, II, 3-9, 51-52, 225,
306-8; III, 197-98; perception and
conception in, II, 299-300; scientific
need for precise. III, 179-80; signs as,
m, 197-99; social factors favoring, II,
295-98; symbols in. III, 215-17, 246,
280; and tools, II, 296-97; unique use
of, by man. III, 266-67; and writing,
III, 148-49

Lao-Tzu, III, 2

LaPlace, Pierre Simon de, II, 7

Latham, R. G., II, 10

Latimer, H. B., I, 105

Lavoisier, Antoine L., I, 56

Laws: causal, I, 97-98; epigenetic mani-
festation of, I, 112-13; of evolution,
I, 95-116; logical, I, 98-99; of phy-

298

INDEX

Laws (continued)

logeny, III, 151; of sense energies, I,
106; systemic, I, 99-106
Laycock, Thomas, Mind and Brain, 11,

189-90
Leacock, E., 11, 158
Leake, Chauncy, II, 221
Leakey, L. S. B., "The Origin of Genus
Homo," II, 17-32;

Adam's Ancestors, III, 159; mentioned,
II, 20, 21, 39, 42, 177, 305; ID,
156
Leakey, Mrs. L. S. B., n, 39; HI, 156
Learned habits, socially transmitted, IT,

335-38
Learning: and communication, IT,
260-62; Darwin on early, 11, 229-30;
evidence against early, II, 400-404
Lederberg, J., I, 88, 315
Legislation of birth control, II, 471-72
Le Gros Clark, W. E., II, 20, 21, 43, 305,

319, 325
Leibnitz, Gottfried Wilhelm von, II, 206
Lemaitre, Canon Georges fidouard, I,

29, 32
Lerins, Saint Vincent of, HI, 21
Lerner, L M.: The Genetic Basis for Se-
lection, I, 527;

mentioned, I, 527, 530, 534; 11, 158
Lesser, Alexander, 11, 182
Lettre, H., I, 617

Levels of subsistence-settlement types:
food-gathering stage, U, 146-49; food-
producing stage, n, 149-50. See also
Life patterns
Lewin, K., II, 384
Lewis, Aubrey, II, 406
Lewontin, R. C, I, 444, 446, 529
Liang Ch'i-ch'ao, and Darwinism in

China, III, 16-17
Life: ancient, I, 123-24; creation of, and
death, I, 40; evolution of, from the in-
organic, I, 46, 52; m, 91, 265-66;
limitation of span of, I, 325; materials
for. III, 57, 69-70, 73-74, 76-78,
97-98, 107; meaning of. III, 71-73,'
83, 107, 111; on other planets, l'
403-4; III, 57, 100-2; organization of,
I, 40; III, 111; uniformity of, ni, 70,
87; universality of, I, 31, 81- Hi'
58-59, 102
— Origin of: conditions necessary for
III, 70, 77, 92; de novo, I, 1 73-74'
discussed scientifically, I, 39-84; m'
265; effect of polarized light on'. III,'
88; as evolution on planet surface l'
29; experimental approach to, I, '42'

spontaneous, HI, 91; theories of, I, 43;
II, 7; III, 104; time between formation
of earth's crust and, III, 77, 81-82
Life-cycles: alternation of sexual and
asexual individuals in, I, 321; develop-
ment of new types of, I, 210; homolo-
gous theory of, I, 211-12; metagenesis
defined, I, 321; phylogenetic relation-
ships between types of, I, 210-17, 298
Life-patterns: on American Plains, II, i
121-22; Arctic hunting, II, 122-23;
basic New World, II, 112-13; collec-
tors of North American Desert, II,
118-20; collectors of North American
Woodlands, II, 120-21; cultivators of
Nuclear America, II, 124-27; early
post-Pleistocene hunters, II, 118; other
hunting and collecting, n, 121-24;
Pleistocene big-game hunters, II, 117-
18; Pleistocene gatherers in New
World, II, 116-17
Lillie, R. S., II, 213
Limeworks Cave site, II, 39, 40
Lindauer, Martin, I, 375
Lindegren, C, I, 619
Lineages, unequal rates of progress of, I,

167
Linnaeus, 11, 8, 11, 404
Linnean Society of London, I, 6; III, 62,

273
Lissman, H. W., I, 363
Lithic stage in New World culture, II, 134
Living cell: condensations in, I, 73; use
of intermediates by, I, 73; use of syn-
thetic pathways, I, 71
Living organisms: constituents in, I, 54;
differ internally from medium in which
they live. III, 98
Lorenz, Konrad, I, 596, 605, 607; II, 229;

III, 190
Lotka, A. J., I, 433, 434
Lovejoy, A., II, 91
Lubbock, Sir John, 11, 1 1 and n., 12
Lungs: development in fishes. III, 136; as

preadaptation, I, 366
Luria, S. E., I, 410
Lussier, J. J., II, 215
Luther, Martin, HI, 36-37
Lwoff, Andre, I, 88, 90
Lyell, Charles: Antiquity of Man, II, 289;
and Darwin, I, 5, 6, 7; influence on
Spencer and Darwin, 11, 207; influence
on Wallace, I, 7; Principles of Geology,
n, 207; mentioned, I, 9, 118; II, 201;
III, 63
Lytic behavior, and lysogenic, I, 92
Lysenko, T. D., II, 221-23, 226

INDEX

299

Lysogenized cell, transduction of genetic
characters to, I, 88

Maarleveld, G. G., II, 59
MacArthur, Robert, I, 565
Machiavelli, IH, 223
McLaren, L. C, I, 86
Macrocomparison, and microcomparison,

in behavior, in, 189-90
Macromolecules: composition of, I, 72;
and evolution, I, 62; III, 83; in protein
synthesis, I, 63; replication of, I, 31,
57, 71; in, 70, 85; separation and selec-
tion of, I, 72; study of, I, 59-64; time
element in production of, in, 87; vi-
ruses reflect organization of, I, 91
Macrophysical realm, interaction of, with

microphysical processes, I, 97
Macy Conferences on Cybernetics (1946-

51), n, 393
Madro-Tertiary plants, I, 274-75
Magnimutation, I, 149, 159
Magnolian alliance, I, 234-36. See also

Angiosperms; Geoflora
Magoun, H. W., "Evolutionary Con-
cepts of Brain Function FoUovi'ing Dar-
win and Spencer," II, 187-209
Maize, Asiatic varieties of, n, 69-70. See

also Crop plants
Maladaptation: appearance of, III, 267;

problem of, m, 269
Malecot, G., I, 462
Malinowski, B., II, 73
Malthus, T. R.: An Essay on the Principle
of Population, I, 5; opposition to, n,
433; mentioned, I, 9, 550; H, 207
Malthusian parameter, I, 433, 442
Malthusian propositions, I, 559
Man: brain of, m, 166-69; biological
status of, I, 19; IH, 145, 146, 173-74;
characteristics of, I, 24-27, 28; ni, 110,
215, 253, 266-67; dating of, n, 57-66;
ni, 163-64; ecology of primitive, in,
145, 165-66, 169; evolutionary proc-
esses in. III, 147-49, 204, 254; fossil,
in, 145, 166-74; future of, n, 392-94
in, 49-61, 146, 169, 173-74, 252, 259
freedom from environment of, I, 408
n, 247-49; origin of, I, 112; n, 30-31
m, 151; pedomorphism in, in, 169-70
place in universe of, I, 25, 28; ni, 57
252; primate features of, n, 35, 52-53
m, 149-51; psychosocial grades in his
tory of, ni, 230-31; sites of early, HI,
160-61; survival of, I, 27; n, 423-24
systematics of, IH, 145-57; Western

and Chinese ideas of, m, 9. See also
Culture; Evolution, human; Primate;
Social structure
Manganese, in photosynthesis, I, 55, 77
Margalef, D. R., I, 565
Marine animals, I, 155
Marler, P., I, 607

Mars: algae and fun^i on, I, 28; condi-
tions on, I, 28, 80; life on, I, 28; HI, 54,
101; travel to, I, 28, 403; III, 102
Marshall, A. W., II, 400
Martyr, Justin, III, 33
Marx, Karl, II, 172
Marx-Engels view of society, n, 89
Marxist model, n, 95
Mason, Brian, I, 563
Mason, H. L., I, 554
Mason, R. J., m, 158
Materialism: as equation of prosperity
and happiness. III, 55-57; in natural
sciences, I, 41
Mather, Kenneth, I, 330, 504; ni, 126
Matter: definition of, I, 41-42; III, 72;

evolution applies to all. III, 102
Mauer, site of oldest dated appearance of

man in Europe, in, 161
Maya culture, n, 133
Mayr, Ernst, "The Emergence of Evolu-
tionary Novelties," I, 349-80;
mentioned, I, 119, 390, 421, 422, 461,
510, 524, 526, 534, 535, 595, 599; n,
225; ni, 107-43 passim
Mead, G. H., n, 378
Mead, Margaret, n, 386, 387
Medicine: history of, and evolution, m,
181; and psychiatry, advances in, H,
314-16, 380, 408-9
Meggers, Betty J., 11, 144
Mehlbere, H., I, 45-46
Meier, Richard, n, 451
Meisel, M. N., I, 618
Melanism: industrial, I, 193-94, 399, 436;
ni, 113; investigation of, I, 181-96,
386-88
Mencius, m, 9, 10, 14, 17
Mendel: Darwin's opinion of, I, 16; effec-
tiveness of laws of, I, 113; investiga-
tions by, I, 478; law of segregation of,
I, 413; objections to theory of, I, 389;
mentioned, I, 16, 43; II, 2
Mendeleyev, Dmitri, periodic table of, I,

Mendelian: analysis, model of, I, 533;
genetics, 1, 200, 315, 386, 400, 413, 532;
inheritance, I, 532-34, 541, 542; neo-
Mendelian theory, I, 386, 389, 524;
population, I, 314, 336, 413 and n.;

300

INDEX

Mendelian (continued)

process, HI, 119; ratio, I, 430; recom
bination, cause of, I, 415
Mendelism: early followers of, I, 350
355; and natural selection, m, 188, 268
385; rise of, I, 385
Mental: apparatus (Freud), II, 196-99,
capacities (Darwin's theory), I, 11; dis-
orders, n, 385-94, 404-7; HI, 179
health, II, 385
Meromixis, I, 200-202
Merrill, E. D., II, 71
Mertz, David B., I, 331
Mesophytic, I, 166
Mesozoic seed plants, I, 230, 236
Metabolism: anaerobic to aerobic, m, 97;
in man, m, 151; mechanism of sugar,
I, 55-56; processes in, HI, 177; sapro-
phytic form, as primitive, I, 204; unity
of, in living world, I, 52-56
Metagalaxy: expansion of, I, 37; scatter-

mg in, I, 33; mentioned, I, 29
Metagenesis, meaning of, I, 321
Metal complexes, I, 76
Metamorphosis, I, 43
Metaphysics, I, 45
Metcalf, M. N., I, 622, 623
Metchnikoff, Ilya, I, 615, 627
Meteorites, III, 103, 104
Methanes, I, 69; III, 96-98
Mexican agronomists, II, 69
Meyer, Adolf, n, 387
Michurinist doctrines, I, 527
Micrococcus strain, grown heterotroph-

ically, I, 78 ^

Micro fossils, bias in favor of, I, 129
Microliths, post-Azilian Meso'lithic H 105
Microorganisms: genetic recombination
in, I, 201; remodeling of genetic plan
m, I, 56; reproduction in, I, 199-217
Microphysical processes, I, 97
Middle Ages, n, 88; HI, 37, 44 181

^sS-s^^^' '' ^^' ^^^- ^"' "'''' ^"'^'^^^^^
Miller, Stanley, I, 70-71, 75; HI, 57 76-

11;.^^^"^^ ^^""''^' ^°2. 265. See also
Urey, Harold C.

Mimicry, I, 16, 495, 562; HI, 129
Mmd: aspects of, HI, 175; basis for, m,
if m'^^T ';TS"'''°" ^f f""^tions
m I?'i ^' '^f''"'"^ ^'"""^ behavior,
111, 46-48; development of, m, 45 204-
and evolution, HI, 182, 186, 266-67-
role m animals, HI, 252; and soul, HI,'
45; studies of, HI, 179-84, 202-6 259-
60; and subjective experience, HI, 47_

Minding: in classification of species, n,
244-46; concepts of, n, 239; and con-
ditioned reflex, Ef, 247-49; principle of
regression, II, 251-53; types of, 11, 243-
50
Miocene: Brandon flora, I, 266; deposits

II, 21; forests, I, 263
Mithraism, III, 228
Mitosis: evolution of complexity of, I,

199; and meiosis, I, 207
Mivart, St. George: antiselectionist op-
ponent of Darwin, I, 354-55; men-
tioned, I, 365, 367, 376
Mohorovicic discontinuity, I, 283
Molecular dimensions, operations in I

89-90
Molecular weight, for range of polymers,

I9 / z
Molecules: accidental synthesis of, I, 66;
atoms in, I, 65-66; reproduction of, I,
58; self-duplicating, I, 63
Monboddo, Lord, II, 296
Monroe, Alexander, n, 187
Montagu, M. F. Ashlev, 11, 341
Montesquieu, Baron Charles de, II, 91
Moore, B., I, 43-44
Moral sense, Darwin on the, I, 12
Morgan, H. L., n, 10, 11, 15
Morgan, Lewis H., I, 409; II, 91, 95 155

172
Morgan, Lloyd: Animal Life and Intelli-
gence, n, 270; An Introduction to Com-
parative Psychology, I, 15, 389; 11, 159
270-71
Morgan, T. H., II, 223
Morgan-Engels-Marx model, 11, 95
Morgan's Canon, n, 270
Morphogeny, I, 172-74
Morphology: and behavior, I, 599-600;
changes in, I, 167; of the jaws, H, 303;
and paleontology, I, 523-45
Morris, D., I, 596
Moscona, A. A., I, 308
Moscow International Symposium, I, 39

41, 46, 58, 64, 77-78
Mother-child separation, n, 395-97
Mottram, J. C, I, 622, 623
Mountcastle, Vernon. II, 235
Mount Palomar, n, 87
Mousterians: at Ehringsdorf, H, 101- at
I'Hermitage, H, 102; of La Quina,' H,

Muller, Max, n, 290, 291, 292 299 307

Muller, C. H., I, 342

Muller, H. J., "The Guidance of Human

Evolution," n, 423-62;

Out of the Night: A Biologist's View of

INDEX

301

the Future, 11, 403; mentioned, I, 15,
213, 423; II, 223, 465; ffl, 42, 69-105
passim, 207-43 passim

Munsterberg, Hugo, II, 270

Miinster Institute, I, 103; HI, 167

MuRALT, Alexander von, "A Decisive
Step in Evolution: Saltatory Conduc-
tion," II, 211-18;
mentioned, U, 232; HI, 175-206 passim

Murdock, George P., U, 81, 175, 179, 182,
327

Murray, Gilbert, II, 13

Murray, John (Darwin's publisher), I, 4

Muscle phosphagens, I, 572

Mutations: atomic, I, 34; characteristics
of, I, 102, 103, 410; HI, 80, 81, 119;
definitions, I, 354-57; direction of, I,
95, 102-3, 159-61, 170, 171; effects of,
I, 91, 103, 173, 202, 409-10; m, 121-
22; as an evolutionary process, I, 197;
349-80 passim, 409-11; in, 108; limi-
tations on, I, 95, 102-3; replication of,
ni, 73, 75, 79; and selection, I, 171,
356-57; single, I, 356; as source of vari-
ation, I, 386, 409; ffl, 114-17; spon-
taneous, I, 102; studies in, I, 409; types
of, I, 102; in viruses, I, 92. See also
Saltation
Mutationism, theory of, I, 354-56
Mutualism, symbiotic, I, 334
MyeHn sheath, II, 211-18 passim

Nagai, S. and H., I, 619
National Museum of Denmark, II, 89
Natural Selection (Darwinian): action
of, I, 319, 341, 349, 376, 418, 419, 532;
basis of, ffl, 71, 82, 116-20; and chem-
ical, in, 82; in evolution of first living
cells, I, 12, 52, 340, 405; ffl, 75; influ-
ence of, I, 513-17; III, 148; interpreta-
tion of, I, 535; theory of, to theologian,
ffl, 24; Wallace's theory, contrasted
with, ni, 120-21. See also Selection
Nature-nurture controversy, I, 385; U,

277-80; III, 182
Naylor, A. F., I, 331
Neanderthal man, U, 34, 99, 304; ffl, 146,

167
Neolithic cultures, H, 82, 90, 109
Neoteny, n, 339-44; ffl, 170
Nervous system: action of, I, 573-74;
conduction of impulse in, n, 211-21;
in, 183; co-ordination in, II, 192; and
fixing experience, II, 260-61; organiza-
tion of, n, 188-89
Neuroanatomy, pioneers in, n, 199

Neurological: mechanisms, n, 211-18;
ffl, 201-2; thinking, influences of Dar-
win and Spencer on, n, 204-8
Neurological Institute in Frankfurt, Ger-
many, n, 199
Neurophysiologist, work of, ffl, 182-83
Newell, Norman, I, 524
New Testament, ffl, 23, 31, 33, 34, 39
Newton, Alfred, I, 7 and n.
Newton, Isaac, II, 7, 379, 404; ffl, 60
Newton's Laws, n, 206
New World culture: evolution of, H, 134-
46; life-patterns in, n, 116-36; subsist-
ence efficiency of, n, 112, 129-30; sub-
sistence types native to, II, 113-14
Nicholson, A. J., "The Role of Popula-
tion Dynamics in Natural Selection," I,
477-521

mentioned, I, 434; ffl, 107-43 passim
Nicolai, J. J., I, 597, 598
Nietzsche, Fr., n, 221; ffl, 9
Nissen, Henry, n, 314, 351, 360, 385, 386;

ni, 196
Nitrogen bases, in DNA, III, 74
Nitrogenous wastes, I, 572-73
Noailles-types burins, II, 104, 105, 106
Noire, Ludwig, on Miiller and Darwin,

n, 291, 298
Nomenclature. See Classification; Termi-
nology
Noosphere, II, 253
Normality, U, 385-88
Northrop, F. S. C, H, 391
Novae, or exploding stars, I, 26. See also

Stars
Nuclear America: cultivators of, U, 124-
27; development in, II, 135; tradition
of, n, 129
Nucleic acids: arrangement of. III, 70,
83, 84, 89-90; chains of, I, 63, 71; selec-
tion for configuration, I, 66; work of, I,
54, 64; III, 73, 80
Nucleoproteids, importance of, I, 102
Nuffield Foundation, I, 181
Nutritional patterns, I, 574-75
Nymphaline butterfly, I, 182-83

Oakley, Kenneth P.: Man, the Tool
Maker, U, 322; mentioned, H, 57, 305,
330

Oberg, Kalervo, H, 175

Occam, William of, I, 188

Oedipus complex, n, 341

Oldowan culture, U, 24, 26, 27; ffl, 158-
59

Old Stone Age, II, 93

Old Testament, III, 23, 25, 30, 31

302

INDEX

Olduvai Gorge, H, 18, 24, 25, 26, 38, 39,

40, 42
Olson, E. C, "Morphology, Paleontol-
ogy, and Evolution," I, 523-45;
mentioned, III, 107-43 passim, 273
Ontogeny: determines phylogeny, III, 124;
modifications through. III, 170; publi-
cations on proportions, I, 105; restric-
tions on alternations, I, 103; shows re-
capitulation of phylogeny, I, 103

Oparin, A. I., I, 58; UI, 76, 265

Oppenheimer, J. Robert, II, 391; III, 91,
202

Optical: activity, I, 52, 66; isomers, I, 72

Organic compounds: accumulation of,
III, 70; elements in first, III, 90; use by
living things, I, 68; III, 97-98

Organic evolution. See Evolution, organic

Origin of life, I, 23-93 passim

Origin of new structures. See Changes;
Direction in evolution; Evolution, nov-
elties in

Origin of Species: biological importance
of, I, 118-19; changes in later editions,
I, 10, 14, 365-67; Darwin Centennial
Celebration, III, 271-82; initial reac-
tion to. III, 24, 29-30; integration of
facts since, I, 528-29; III, 251; publica-
tion history of (J. Huxley), I, 1-21

Original sin, HI, 30

Orion, bright stars in, I, 37

Orthogenesis, I, 15, 167, 168, 404

Orwell, George, 1984, H, 396

Overdominance, genetic, I, 440-41

Owen, Sir Richard, I, 119

Oxygen: in atmosphere, I, 75; III, 96; de-
velopment in air, I, 55; evolution of, I,
77; in era of photosynthesis, I, 78;
methods of increase in, I, 75; photo-
synthesis as source of, HI, 97; transport
of, I, 571

Ozone, in atmosphere, I, 75-76

Paleoecology, defined, I, 562

Paleolithic cultures, II, 99-110, 172

Paleontology: and evolution, I, 537-43;
new fossil material in, n, 313-14; study
of paleoecology in. III, 142

Paleophytic, I, 166

Paleozoic, plants in the, I, 228, 230, 233

Palerm, Angel, II, 175

Paley, William, HI, 30, 45

Palmer, L. S., II, 304, 306

Parallel evolution: with adaptive radia-
tion, I, 170-71; and theory of direc-
tional mutation, I, 159-60

Parallelism, I, 98, 168-70, 538

Parasexual phenomena, in viruses and
bacteria. III, 115-16

Parasite-host relations, I, 322

Park, Thomas, I, 311, 331

Parthasarathy, N., II, 68

Parthenogenesis, II, 453-54

Pasteur, Louis, I, 43; II, 454; III, 91, 99

Patterson, Brian, I, 467, 524, 537

Paul, Leslie, II, 289

Pavlov, Ivan P.: on ability of individual to
adapt, II, 236-37; Autobiography, II,
193; conception of language, II, 225; on
conditioned reflex, II, 194; and Dar-
win, II, 219-38; extension of concepts
of, II, 232-36; on human types, II, 224-
27; influence of Darwin and Spencer
on, II, 193-95; on inheritance of ac-
quired characteristics, II, 221-24; and
Lamarckianism, II, 221-22; Lectures
on Conditioned Reflexes, II, 224; re-
search after, 11, 230-36; mentioned, 11,
188, 223, 232, 235; III, 180, 199

Pavlovian Laboratory of the Johns Hop-
kins University, II, 219 n., 232; III, 180

Pearl, R., I, 327

Pearson, Karl, I, 430; II, 277

Peck order. III, 166

Pedcmorphism, III, 108, 169-70

Pekin man, II, 38, 42, 46; III, 161, 166

Pelikan, Jaroslav, "Creation and Cau-
sality in the History of Christian
Thought," III, 29-40 J

Penck, A., n, 59; HI, 162 \

Peptides, I, 59, 72

Perception, research in, 11, 379

Perdeck, A. C, I, 607

Perfection, Chinese concept of, m, 9

Perigordian industry, II, 104, 107

Personality: psychoanalytical theory of,
n, 314—16; problems in, structure. III,
203

Phenotypes: changes in, as result of en-
vironmental stress. III, 142; Darwin's
concentration on, I, 16; differences
among, I, 358; operation of, in natural
selection, I, 376; relation to genotypes,
I, 349

Photosynthesis: based on light absorption
by metal complexes, I, 76; era of, I, 78;
manner of achieving results, I, 77;
source of oxygen. III, 97; use of organic
compounds formed by. III, 97-98

Phylogeny: alteration by mutations, I,
102, 103; determined by ontogeny, III,
124; experiment in sampling, I, 150;
human, 11, 312-13, 318-19; processes,
I, 96; psychic phenomena in course of,

INDEX

303

I, 98; recapitulation of, I, 103; relation-
ships in chromosomal cycles, I, 209;
and uniqueness of individual, I, 95
Physiological: biology, I, 381; characters,
I, 572-76; genetics, I, 429-75 passim;
laws, I, 105
Pickenhain, Lothar, IT, 230
PiGGOTT, Stuart, "Prehistory and Evolu-
tionary Theory," II, 85-97
Pigments, formation of natural, I, 76
Piltdown man, 11, 313
Pincus, Gregory, II, 453
Pirie, N. W., I, 40
Pisarev, and Pavlov, 11, 193
Pithecanthropine forms, II, 40
Pittendrigh, C. S., I, 119, 175 n., 341
Plainview points, II, 118
Planck, Max, II, 443

Planets: biology of, I, 28; births of, I, 30;
life on other, I, 28, 79, 80, 403, 426;
III, 57, 64-65, 70; sterility of, I, 79;
theory of origin of. III, 95
Planned Parenthood International Con-
ference, III, 50
Plants: adaptive features of ecotypes, I,
15; alliances of, in terms of environ-
ment, III, 140; alternation of genera-
tions in, I, 211; attitudes toward orna-
mental, II, 77, 79-81; flowering, evolu-
tion of, I, 227-305; insular. I, 277-93;
III, 139; migration of, I, 256, 279; pearl
millet, II, 78, 79, 81-83; transmission
of, from Africa to India, II, 77-79; in
Triassic and Jurassic, I, 236-37. See
also Crop plants; Grains
Plate, L., I, 360

Plato, I, 354; II, 225; HI, 33, 228
Playfair, I, 118
Pleiades, I, 38

Pleiotropy, I, 103, 437; HI, 118
Pleistocene: evolution of man during, 11,
33-56; fossil beds, II, 31; gatherers and
hunters, II, 117, 130; records in glaci-
ated areas, II, 58; sediments covering,
n, 59-64; survival in Early, I, 27-28
Pliocene: carnivores, I, 111; environ-
ments invaded since. III, 136; forerun-
ners of European plants, I, 262-63;
fossil beds, II, 31; reduction in species,
I, 262
Plio-Pleistocene boundary, 11, 62
Poebel, A., II, 162
PoLAK, Fred, III, 207-43 passim
Poly-amino acids, I, 71-73
Polygenic characters: in isolation, I, 183-

84; studies of, I, 188-89
Polyisomerism, I, 173

Polymers, I, 66, 72; HI, 80-81

Polymorphism: in Batesian mimicry (but-
terflies), I, 191-93; changes observed
in, I, 184, 440; definition, I, 189; and
rapid evolution, I, 189-95; and snail
markings, I, 190-91

Polypeptide synthesis, I, 72

Polyploidy, multipUcation of species
through. Ill, 132

Population (s): adaptation in, systems, I,
307-48; animal aggregations in, I, 312-
13; anti-Malthusians on, II, 433; and
communities, I, 551-52, 556-57, 562-
67; composition of, I, 311; control of,
n, 468-72; IH, 49-55, 238-42, 258;
corrective forces of. III, 50; defined, I,
310, 550; determination of a species in,
I, 351; distribution of lethals in wild,

I, 468; dynamics, I, 478, 501-5, 518-
19; lit, 129-30, 141-42, 188; in ecol-
ogy, m, 165; ecology of, I, 429-475
passim; and environment, I, 424, 479;
n, 384-85; evolution in, I, 181, 316-18,
320-21, 325-29, 333-34, 407; explo-
sion, I, 184; II, 463-64, 471-72; III,
49-55, 64, 145, 258, 489; future world,

II, 472-73; and eenetics, I, 313-14.
422, 440; III, 140-42; of geographically
mixed cridn, I, 423; and industrializa-
tion, in, 50-53; and individuals, I, 443,
561-62; integration, I, 316, 322-25,
335-40; life cyc'e of, I, 321-22; Men-
deUan, I, 313-15; the new heredity in,
n, 464-66; non-genetic transmission
of change in, I, 586-87; polymorphism
in, I, 440; potential variability in. III,
119; problems of, HI, 49, 53-54, 61,
142, 143; selection in, I, 184, 319. 407-
8, 480-92, 499-501, 507; III, 120-22,
141-42; speciation in, I, 517-18; sta-
bility of, I, 481, 519; structure, I, 462,
467-68, 557-62; time axis in develop-
ment and growth of, I, 310

Population systems, evolution of adapta-
tion in, I, 307-48

Porphobilinogen, condensation of, into
tetrapyrrole, I, 73-74

Porphyrins: characteristics of, I, 74; com-
pounds in primitive systems, I, 77; de-
rivatives, structure of, I, 55; early ap-
pearance of, I, 74; evolutionary role of,
I, 74-76; origin of, I, 73-75; III, 94;
as source of energy, HI, 95; synthesis
of, I, 74, 76; uses of. III, 99

Portmann, A., I, 105

Pradel, J. H., II, 101

Pradel, L., II, 101

304

INDEX

Preadaptation: concept of, I, 364-67,
371; in human evolution, HI, 197

Prediction: of gaps in fossil record, I,
150-52; importance of, for fossil ani-
mals, I, 111; of structure and func-
tions in new species, I, 110-11

Prehistory: ambiguities of basis of, 11,
93-96; cultural activities in, II, 143-46;
defined, 11, 86; and evolutionary
theory, 11, 85-97; interpreting, II,
92-93; models of, II, 89-96, 143-51

Price, Derek, U, 91

Primates: behavior of, m, 165-66; be-
havioral evolution of, n, 360-61; bra-
chiation. III, 152-54, 204; brains of,
n, 343-44; dentition of, 11, 37-38,
47-48, 155-56; fossil, n, 17-56; ID,
151-63; invention among, HI, 196-97;
language, H, 330-31, 353-54; HI,
193-99; man as a, n, 35, 52-53; III,
145, 149-51; modern distribution of,
n, 18; social structure among, n,
329-38; tails of, HI, 154-55; tool-using
in, m, 296-97

Primeval Atom theory, I, 29, 32, 33, 34

Primitivists of 18th century, II, 95

Primordial cells: emergence of entire
class of, I, 51; minimum requirements
for, I, 64; as survivors of quasi-living
things, I, 66

Procaryota: evolution of genetic systems
in, I, 205-7; and Eucaryota, I, 200-
207; intracellular differentiation in, I,
203; mode of life of, I, 203-7

Progress: biological, in series of steps,
III, 249; idea of human. III, 207; origin
of human social, HI, 212; pre-Darwin-
ian social thought on, n, 5-6; tech-
niques involved in, HI, 114

Prosser, C. Ladd, "Comparative Phys-
iology in Relation to Evolutionary
Theory," I, 569-94;
mentioned. III, 69-143 passim

Prosthetic group, I, 54-55, 58

Proteins: amino acids in chains, I, 59-63;
chemical and serological investigations
of, I, 95; function as enzymes, I, 54-55,
71; growth by polymerization. III, 83-
in living things, I, 54; III, 73, 87-88-
molecule, I, 61, 62; proof of types of'
I, 95; specificity, I, 95, 575-76; syn-
thesis, I, 59, 63, 71, 72; III, 83; in
viruses, I, 86
Proteolytic enzymes, I, 573
Proto-agriculture, beginnings in Africa

n, 82

Protohistory, time of, II, 85-87

Protostars, character of, I, 37
Protungulata, origin of hoofed animals
from, I, 108

Psychiatry: concepts of, II, 374-85; con-
tributions to, by evolution, II, 373-85;
and instincts, II, 380-81; and medicine,
n, 408-9; research in, II, 376, 378-79,
388-95; studies in social, II, 404-7

Psychogenesis: concept of, I, 113; in
evolutionary research, I, 97

Psychology: comparative studies in, 11,
271-74; functional, II, 280-85; hered-
ity-environment controversy in, II,
277-78; influence of Darwin on mod- J
ern, n, 269-80; laws of, II, 283-84; \
means and correlation coefficients in,
II, 278-80; schools of, II, 280; study
of emotional expression in, II, 274-77;
study of individual differences, II,
277-80

Psychosocial evolution, HI, 217, 242. See
also Evolution, cultural

Pumphrey, R. J., II, 322

Puritanism, III, 223 J

Putjang beds of Java, II, 40, 43 \

Quantification of science, II, 284
Quenstedt, Johann Andreas, III, 37
Quetzalcoatl-Topiltzin, II, 162

Radiation, adaptive: I, 161, 170-71,
237-43; combination of processes in,
I, 162; examples of, I, 162-63; and ex-
tinction, I, 161-66; primary, I, 165-66;
relaying, I, 165

Radiation, atomic: alterations in stars af-
fecting, I, 24; from decay of radioactive
elements. III, 94; destruction of germs
in space by. III, 103; green alga re-
sistant to, I, 79; in starshine, I, 24;
survival of bacteria after. III, 90-91

Ramsay, J. A., I, 560

Random: action, I, 68-69; drift. III, 108;
processes, and directed, I, 462

Rashinsky, S. A., translator of Origin
into Russian, II, 195

Rate function, time course of, I, 584

Rationalism, II, 1

Razran, Gregory, "Pavlov and Lamarck,"

n, 222

Reaction systems, formula for, I, 438

Reasoning, not demanded in primitive
times, I, 27-28

Rebirth, and reincarnation. Eastern con-
cept of. III, 253

Recapitulation: first explanation by Dar-

INDEX

305

win, I, 12; Haeckel's law of, III, 124;
mentioned, III, 108
Recombination: increases variability, III,
114; as revolutionary process, I, 197;
III, 108; in viruses (bacteriophage), I,
200
Redfield, Robert, U, 111, 163; III, 273
Reformation: codifiers of thought in, III,
37; existentialist thought in. III, 36;
mentioned, II, 467
Regan, C. T., I, 363
Relaying: delay of, I, 164-65; in in-
crease of taxa, I, 156; expansion as
reoccupation, I, 162; in extinct groups,
I, 164; of invertebrates by vertebrates,
I, 157; in nearctic ungulates, I, 156
Religion: characteristics of. III, 228; defi-
nition of, III, 48-49; evolutionary de-
velopment of, ni, 253; future, III, 260;
and science. III, 257. See also Roman
Catholic church
Rensch, Bernhard, "The Laws of Evo-
lution," 95-116;

mentioned, I, 357, 405, 412, 413; III,
145-74 passim
Replication: of chromosomes, III, 79;
continuation of. III, 8 1 ; of nucleic acid,
I, 89; of DNA molecules. III, 93; self-,
III, 7
Reproduction: alternation of generations
in, I, 207-17; II, 454; bacterial, I,
91-92; chromosomes in, I, 199-207;
and enzymes, I, 71; exact, I, 57; as
measurement of survival value, I, 340;
molecular level, I, 57-64; motivations
in, II, 436-38, 445-47; nature of, I,
56-64; parthenogenetic, 11, 453-54;
processes in. III, 177; selection in hu-
man, II, 447-52; sexual, as source of
variation, I, 413-17; techniques in se-
lective, II, 452-56
Reptiles, expansion of, into terrestrial

habitats, I, 157
Respiratory mechanism, in cancer cells,

I, 616-18
Reverberation, III, 204
Revolutions: in culture. III, 229; origin
of. III, 229, 230; religio-philosophical,
III, 228; scientific-technological. III,
228-31
Rhodesian man, 11, 304
Richmond, I. A., II, 92, 96
Ritualization, adaption to signaling func-
tion, I, 601
RNA: and DNA, distinction between,
III, 84; and DNA, involved in cellular
activity. III, 85; molecules of. III, 107;

produced under influence of DNA, HI,

142; role of, I, 87
Robbins, R. B., I, 430
Robertson, J. D., II, 214-15
Robinson, J. T., U, 19, 29, 37, 40; III,

158
Robson, G. C, I, 550
Rockefeller Foundation, II, 69
Roe, Anne, II, 357, 386
Roheim, G., II, 341
Roman Catholic church: on birth con-
trol, II, 471; Fathers of. III, 21, 59;

history of attitude toward evolution,

m, 19-28
Romanes, G. J., II, 270, 310
Romans (in Bible), III, 37
Romer, A. S., I, 370, 524, 536
Rorschach test, II, 383
Rosholt, John N., Jr., H, 60; HI, 163
Rostand, Jean, 11, 402
Royal Anthropological Institute, III, 271
Rubin, M., H, 59
Rushton, W. A. H., II, 215
Russell, E. S., II, 299
Russian: attitude toward Darwin, II, 221;

early translations, II, 195
Russkoye Solvo, II, 193
Rutherford, Ernest, II, 443

Sackett, W. M., II, 58

Sacred trees and groves, 11, 80

Sages: characterization of. III, 11; con-
cept of. III, 13-14; as proponents of
unequaled perfection, III, 9-13; sug-
gest Chinese evolutionary thinking,
III, 11-15

Sagittarius, frequency of novae in, I, 26

Sagon, Carl, III, 104

Sailer, K., I, 105

Salt, G. W., I, 110,331

Saltation: as an evolutionary phenome-
non, I, 149; not needed to explain fos-
sil record, I, 528; as origin of novelties,
I, 354-57

Saltationism: arguments against, I, 350,
356; on new structures, I, 340-50;
theories of, I, 354-56

Saltatory conduction: II, 213-17; III, 183

Sandia: and Clovis projectile points, II,
117; complex, 11, 130

Sankhya philosophy. III, 228

Sanskrit, II, 8-9, 78

Sapir, Edward, II, 301, 393; III, 179, 194

Satyrine butterfly, Maniola jurtina, I, 184

Sauer, F.: I, 598; H, 76, 77; Agricultural
Origins and Disnersals, II, 77

Sauer^ Jonathan D., H, 70, 71

306

INDEX

Sax, K., n, 68

Saxena, B. B., I, 110

Scandinavian culture, 11, 253

Schaeffer, Bobb, I, 359, 537

Schindewolf, O. H., I, 528

Schizokinesis: Darwin's observations on,
II, 227-28; research on, II, 234-35

Schlabritzky, E., I, 105

Schleiermacher, Fr. Ernest, III, 38

Schmalhausen, I. I., I, 413 n., 535

Schmidt, Father Wilhelm, HI, 234

Schmitt, Karl, ffl, 273

Schneirla, T. C, II, 312, 353, 359

Schramm, G., I, 87

Schrodinger, E., I, 50 n.

Schultz, A. H., II, 329

Science, III, 101, 104

Science(s): biological, I, 117; III,
249-51; definition of general, n, 2; III,
210; interdisciplinary, I, 47, 49; ma-
terialistic approach of, I, 39-44; and
philosophy, pervaded by Darwinian
theories, II, 290-91; and politics, III,
59; problems in, I, 173-77; and re-
ligion, I, 382-83; III, 19, 247; static
until 1859, III, 212; universality of, I.
46-48 ^

Scientific interpretation, of an organism,

Scientific knowledge: limitations of, I,
44-50; specialization in growth of. III,
246; inference, III, 186-87; observa-
tion, III, 185-86; quantification, II,
284; III, 188-89;

mentioned, I, 532-34; II, 375 397_
400; III, 185-87, 205

Scientific Revolution, II, 466

Scopes trial, II, 1 ; III, 43

Scott, J. P., II, 335

Scottish Primitivists, 11, 90

Scottsbluff points, 11, 118

Scyphozoans, I, 152

Sears, Ernest, II, 76

Sears, P. B., n, 59

Sechenov, I. M.: father of Russian phys-
iology II, 194; influenced by Spencer,
H. 195; mfluence on Pavlov, II,
193-95; Reflexes of the Brain, II' 195

Sedgwick, Adam, and Darwin at Cam-
bridge, I, 9

Sedimentation, and fossil preservation, I,

Segregation, Mendel's law of I 413
Selection: aspects of, I, 534;' and behav-
ior, I, 174, 602-5, 610; change in mean-
ing since Darwin's time, I, 532- m
214; by competition, I, 315, 477-8o'

487-91, 496-501; effects of, I, 11, 338,
422, 483, 608-9; m, 89, 108, 125-26;
and eugenics, II, 430-35; III, 242-43;
as evolutionary process, I, 17-18, 190
197, 534; II, 405-8; HI, 108, 123-25;
and genetics, I, 417-22; III, 75; im-
plications of intersexual allaesthetic,
I, 11; in laboratory cultures, I, 480-82;
intragroup, I, 517-18; on level of DNA
molecules. III, 83; positive, through
artificial insemination, n, 449-55;
progress of (in response to ether treat-
ment), I, 395; psychosocial, III, 213,
214; and random sampling, I, 468; re-
cent findings on, I, 107; III, 129-30, in
similar environments, I, 411-13;
theories of, I, 491-92, 524, 530; III,
120-21
Self, concept of, IT, 349-50
Self-awareness, concept of, II, 349-50;

III, 266-67
Self-fertilizing organisms and selection,

I, 198
Self-cbjectification, II, 352-53
Self-regulating systems, complexity and

purpose, I, 57
Self -replication: in evolution, I, 57-58;
mechanism of. III, 79, 80, 83; reap-
pearance of units in, I, 52, 74. See
also DNA
Semantics, III, 46. See also Terminology
Sense: cells, protection of, I, 106; organs,

on other p'anets, I, 31-32
Setchell, W. A., I, 279, 288
Sewertzoff, A. N., I, 357, 359, 360, 366,

367
Sex: adaptation, I, 316, 335; HI, 114-16;
cycles, I, 317; determination, I, 317;
evolution of, I, 315-18; III, 108,
126-27; function of, I, 315; reproduc-
tion and genetic transduction of, I,
316; selection in. III, 120-22; in sterile
castes of termites, I, 320; study of in
evolution and psychiatry, II, 384; types
of, in the fungi, I, 219-20
Sexual recombination, oridn of, I, 201-7
Sexuality, I, 201, 208, 317-18
Shang Ti, "The Supreme Ancestor," III,

13
Shapley, Harlow, "On the Evidences of
Inorganic Evolution," I, 23-38;
mentioned, I, 50, 81, 403; III, 41-65
passim, 69-105 passim
Shemin, D., I, 58, 73
Sheppard, P. M., I, 468
Shotwell, J. A., I, 563
Shrinking-nebula hypothesis, I, 30

INDEX

307

Silicones, stability of, I, 67
Simpson, George Gaylord, "The His-
tory of Life," I, 117-80;
mentioned, I, 405, 413, 450, 524, 526,
528, 534, 535, 537, 541, 563, 564; II,
14, 386, 507; III, 145-74 passim
Sirius, I, 37
Siwe, J. A., I, 105

Size: body and organ, I, 103-5; brain,
II, 324-25, 339-44; III, 157; Cope's
rule on increase of, III, 151; evolution-
ary trend toward larger, I, 172
Skottsberg, C, I, 279, 288
Skulls, sites associated with, 11, 305
Slobodkin, L. B., I, 560, 565
Slonimski, P., I, 619
Slotkin, J. S., II, 87, 88
Small, W. S., n, 270
Smith, A. L., U, 158
Smith, Sir G. Elliot, H, 313
Smith, Homer, I, 352
Snail, Cepea nemoralis, I, 190-91. See

also Polymorphism
Snow, C. P.. I, 40

Soan and Choei-Tong-Keou type indus-
tries, II, 109
Social: behavior, 11, 329-38; concept, I,
319-21; factors in language, II,
295-98; factors in phylogeny, 11,
309-71 passim: structure, I, 18, 319-21,
563-66; H, 130-31, 229, 329-38; III,
171, 178, and see Communities; Popu-
lations
Socrates, II, 377
Sonneville-Bordes, D., 11, 104
Soul, III, 20, 46
South American: collecting patterns, II,

129; flora, I, 259
Space: infinity of, I, 33; material re-
turned to, I, 35; transport of germs
through, III, 70, 103-5
Spanish Conquest, H, 132; III, 227
Spearman, Charles, II, 277
Speciation: adaptations in, I, 580-82; as
a by-product of biological improve-
ment, I, 517-18; environmental fac-
tors in, I, 582-87; isolation as creator
of variety. III, 132-33; physiological
factors in, I, 13, 576-82; III, 109
Species: criteria for defining, I, 577-79;
discovery of new, I, 139; HI, 134; in-
fluence of environment upon, I,
333-34; extinction of, I, 79, 153-54;
forced process for origin of, I, 111-12;
insect, I, 108; HI, 134; morphological
approach to, I, 577; multiplication of,
through polyploidy, m, 132; physio-

logical variations among, I, 577-79;
prediction concerning new, I, 110-11;
reproductive isolation approach to, I,
577; III, 133; sumpatric, I, 334. See
also "comparative" entries
Spectra, I, 29, 31, 76; III, 102
Speech: and brain structure, 11, 50-52;
and communal living, II, 295-96; ear-
liest, II, 294-98, 302-6, 320; pathology
of, III, 179; as special faculty of Homo
sapiens, 11, 293; symbolic behavior in,
II, 293-94, 300-2; tool-making and
tool-using as direct precursor of, 11,
296-97
Spencer, Herbert: and Darwin, 11, 190,
206-7; Essays, II, 205; evolutionary
view of, II, 188, 190-2; "development
hypothesis," II, 191-92, 207; influence
on scientists, H, 190, 195, 204, 211;
on new edition of Carpenter's Princi-
ples of Physiology, II, 190; his Sys-
tem of Synthetic Philosophy, II, 207;
translations of his work into Russian,
n, 195;

mentioned, H, 2, 6, 189, 339; ID, 212,
271
Spengler, Oswald, H, 88, 92
Spiro, M. E., II, 327
Spitz, R. A., II, 396
"Spontaneous generation," III, 90
Spurway, H., I, 461

Stabilization: of marine faunas, I, 157; as
process of evolution. III, 127;
mentioned. III, 109
StaHn, J., n, 298
Stampfli, R., H, 215
Stanley, W. M., I, 85
Stars: alterations in, I, 24; Andromeda
triplet, I, 37; birth of, I, 36-37; build-
ing of, I, 35; clusters of, I, 26; com-
position of, I, 35; counts of, I, 30; ex-
ploding, I, 26; family of planets for
each, III, 101; and galaxies, I, 29; loss
of mass in, I, 38; mean-density series,
I, 37; relation of frequency to distance,
I, 26; of "second generation," I, 35;
size of, I, 37; spectra of, in, 102; tem-
peratures of, I, 34-35, 37; transforma-
tion of fuel in, I, 34-35; in various
continuous series, I, 37; white dwarfs,
I, 37. See also Stellar evolution
Stasigenesis, as mode of evolution, HI,

225
Steady-state hypothesis, I, 33
Stebbins, G. Ledyard, "The Compara-
tive Evolution of Genetic Systems," I,
197-226;

308

INDEX

Stebbins, G. Ledyard (continued)

mentioned in, I, 316, 524, 527; H, 82;
in, 107-43 passim
Stefansson, V., II, 230
Steinheim man, 11, 27, 46, 305
Stellar evolution, I, 36-38
Sterkfontein, II, 22, 29, 38, 48; IH, 158,

163
Stevenson, Adlai, m, 41-65 passim
Steward, Julian H., "Evolutionary
Principles and Social Types," 11,
169-86;

mentioned, 11, 154, 155, 156, 157, 159,
161, 163, 175; IH, 207-43 passim
Stillbay industry, 11, 109
Stoic school, in, 228
Stone Age: crops, n, 78; cultures, n, 19,
24, 25, 26; as model of prehistoric
past, II, 89, 90
Strauss, W. L. J., n, 313, 343
Structure: comparison of, in mammals
and reptiles, I, 168-72; explained by
history, I, 118; novelties in, I, 353;
potential variability of any, I, 375
Studentsov (Pavlov's assistant), II, 223,

224
Stutz, Howard, n, 82
Subsistence types, n, 113-14, 146-50
Sugar cane, n, 68. See also Crops
Sullivan, H. S., n, 383
Sumner, F. B., I, 467
Sun: earlier position in universe, I, 25,
26; and evolution, I, 24, 35, 40, 75; a
"third-generation" star, I, 35; in, 101
Sung period, literary movements in, ni.

15
Superego: formation of, m, 172; in men-
tal apparatus, n, 197-98
Survival, resistance to disease as factor

in, II, 389
Survival of the fittest, Darwin's meaning
of, I, 479 ^

Sutherland, Alec, m, 263-70 passim
Sutter, E., I, 105
Sverdrup, H. U., I, 559
Swanscombe skull, n, 64, 305; m 163
Swartkrans, n, 48 '

Swedish deep sea expedition, n, 62
"Symboling," n, 249-50, 353-57- m
208, 215-17 ' '

Symbols: acquired through learning, in,
216; arbitrary in language, ni, '280-
and signs, m, 198-99; use in speech,'

Synecology, I, 549. See also Ecology
Synthesis: as agency in evolution I 35-
of food. I, 204; of organic molecules'

I, 67; of polypeptides and proteins, I,
72; of substances, I, 58, 65; of true pro-
teins and nucleic acids, I, 59

Synthetic biology, nature of, I, 381-82;
pathways, use of by cell, I, 71; reac-
tions, I, 70, 75

Systematic mutation, I, 159

Systemic laws: character of, I, 99; exist-
ence among psychic components, I,
100

Systems, attributes of all, in, 177

Tails, in higher primates, HI, 154-55
Talmudism, HI, 228
T'ang, literary movements, m, 15
Tao, meaning of, m, 2-3
Taoism, in, 228
Tasaki, I., n, 213, 214
Tasmanian industry, n, 109
Tatian, Syrian Church Father, in, 34
Tax, Sol, "The Celebration: A Personal
View," in, 271-82;

mentioned, ni, 41-66 passim, 67-68,
245-49
Taxonomy: criteria for defining species,
I, 577-79; behavioral characters in, I,
609; phylogenetic units in, I, 18. See
also Classification; Speciation; Termi-
nology
Technology, significance for archeology,
n, 95-97. See also Evolution, cultural
Teleonomy ("utility"), I, 175 n., 341; in,

109
Teleost distribution, I, 128
Telepathy, n, 459 n.
Telescope: on Palomar, evidence from,

I, 33; in star counts, I, 30
Teotihuacan civilization, H, 127; m, 227
Terminology: in cosmogony, I, 33; of
culture stages, I, 155; of ecological
units, I, 548-62 passim; scientific need
for better, m, 179-80, 185
— differentiations in: "culture" and
"race," in, 271; "culture" and "so-
ciety," n, 329; "ego" and "self," n,
348-51; "evolution," "cultural evolu-
tion," and "organic evolution," I,
310-11; "historiographer" and "anthro-
pologist," n, 236; "mind" (Huxley)
and "behaviour" (Tinbergen), in,
185, 186-87; "RNA" and "DNA," in,
84-85; "saltation" (I, 149) and "salta-
tory conduction," (m, 183)
Termites, I, 320
Territorialism, m, 165-66
TertuUian: Treatise Against Hermogenes,
in, 34; opposed to Gnostic ideas, HI, 35

INDEX

309

Tetrapyrrole, I, 73-74

Teyjat points, II, 105

Tezcatlipoca, II, 162

Thanatocenosis, definition of, I, 563. See

also Communities
Theism and atheism, I, 383
Theology: Christian, in 19th century. III,

39; recent scientific trends, III, 39-40
Theophilus of Antioch, III, 34
I Therapsid reptiles, acquisition of mam-
mal-like characters by, I, 169
Thinking: evolution of, II, 378-79; pat-
terns in, III, 256; proper, HI, 257; re-
search in, II, 376. See also Mind
Thoday, J. M., I, 504
Thofern, E., I, 78
Thomas, P. T., I, 616
Thomistic theory, of essence and exist-
ence, ni, 36
Thompson, W. N., H, 317
Thomsen, Christian, II, 89, 90
Thorndike, E. L., Animal Intelligence, II,

270
Thorpe, W. H., I, 597
Three Ages, II, 89, 90
Thucydides, II, 3; HI, 223
Thurber, James, III, 114
Tibetan culture, 11, 253
Tilney, Frederick, II, 305
Time: course, I, 585-86; as definition of
evolution, II, 3; dimension, for all or-
ganisms and systems. III, 125; geologic,
I, 166
Timiryazev, K. A., II, 195
TiNBERGEN, N., "Behaviour, Systematics,
and Natural Selection," I, 595-613;
mentioned. III, 175-206 passim
Toltec civilization, 11, 127
Tools: association with Australopithe-
cinae, III, 158-59; behavioral signifi-
cance of making and using, II, 322-325;
evolution of types of, II, 103-4; making
of by hominids, II, 322; III, 145; use
and invention oif, by animals. III, 195-
97
Toynbee, Arnold, I, 408; n, 88, 89, 92
Tradition, doctrine of organic evolution

threat to Christianity, m, 29-30
Transduction, genetic recombination by,

I, 89, 200
Transfer of function, transitional stage in,

I, 362
Transformation: breakthrough to new be-
havior, I, 173-74, 352-53; as evolu-
tionary process, I, 91; III, 109, 127; in
function, I, 173-77; in structure, I,
172-75, 365

Trends, in evolution, I, 166-72

Tresco, the "Farm Area," population in,
I, 185-86, 187

Trewavas, E., I, 363

Trinil beds, II, 17

Trinity, in Aquinas, HI, 35

Triptolemos, II, 81

Trois Freres, cave of, 11, 355

Tsang, III, 17

Tula, n, 162

Tumors: malignant, I, 616-18; in verte-
brates, I, 623. See also Cancer

Twins, studies of, H, 277-79, 400, 407,
454

Tylor, E. B., H, 11, 12-13, 16, 325

Tyndall, J., I, 41, 42, 43

Typostrophism, I, 149, 159

Ultraviolet radiation, I, 70, 79

Uniformitarians, I, 118

Universe: Chinese concept of. III, 6; de-
lineation of, I, 49; existence of life in,
I, 50; III, 58-59; order in, I, 46; origin
of, I, 32-33; HI, 2; physical, I, 118; our
shifting position in, I, 25; III, 57

Urey, Harold C, I, 69, 70, 80-81; H, 60;
III, 57, 76, 77, 93, 94, 162, 265. See
also Miller, Stanley

Urry, W. D., II, 60

Vallois, H. v., n, 43, 51

Values: development of systems of, III,

146, 238-39; primate and human. III,

196; social, in animals, HI, 193-95
Van der Hammen, Th., II, 59
Variation: by genetic drifts, I, 417-22;

random, I, 16, 413-22; III, 116; by

sexual recombination, I, 413-17; III,

117-20
Vaufrey, R., II, 101
Vavilov, N. I., II, 69, 75, 76
Vavilov-Lysenko controversy, II, 222-23
Veblen, Thorstein, III, 236
Veith, Ilza, "Creation and Evolution in

the Far East," ID, 1-17;

mentioned, HI, 175-206 passim, 263-

70 passim
Venkatraman, T. S., H, 68
Venus: conditions on, I, 80; plant life on,

in, 101; mentioned, III, 54
Vertebrates, adaptive types in, I, 242;

land, I, 157
Veterans Administration, psychological

laboratory of, HI, 180
Vickers, G., H, 407
Vico, Giovanni Battista, 11, 88

310

INDEX

Villages, semipermanent, in New World,
n, 115

Vince, M. A., I, 596

Viruses: and bacteria, I, 200; III, 83; con-
tent and function of, I, 85-86, 87, 90;
III, 69, 74, 84-85; and evolution, I, 85-
93; III, 74; forms, I, 91; genetic re-
combinations, I, 200-201; inflections,
I, 87-88; information on, I, 85-89;
intracellular synthesis of, I, 87; muta-
tion in, I, 74, 92; origins of, I, 90; III,
74; replication in, I, 86, 87, 89; III, 74

Visual pigments, varieties of, I, 576

Vitamins, I, 55

Vladimirova, G. B., I, 620, 621, 624, 625

Volterra, V., I, 434

Vulcanism, and fossil plants, I, 274

Waddington, C. H., "Evolutionary Adap-
tation," I, 381-402;
mentioned, I, 15, 316, 317, 329, 505,
534; II, 256, 403; III, 145-74 passim

Wald, George, I, 66; HI, 77

Waldeyer, Wilhelm, II, 199

Wallace, Alfred Russel: characteristics of,
I, 6, 45; contribution of, I, 6; and Dar-
win, I, 1, 10; II, 49; reading of Malthus
and Lyell, I, 6, 7; referred to "animal
populations," I, 550; and theory of se-
lection, I, 1, 491-92; on biota of is-
lands, I, 278

War, psychoses during, n, 401-2

Warburg, O., I, 616, 617, 619

Washburn, Sherwood L., "Human Evo-
lution and Culture" (with F. Clark
Howell), II, 33-56;
mentioned. III, 166, 273

Watson, J. B., II, 271, 281, 536

Watson, J. D., I, 102

Weeds, II, 71-72, 76

Weidenreich, P., n, 46

Weinberg, W., 1,413, 430
Weismann A., I, 315
Weizacker, C. V., I, 50 n.
Wenner-Gren Foundation, ni, 272
Westermarck, Edward, II 332'
Westoll, T. S., I, 524, 536, 537
Wheeler, R. E. Mortimer, II, 94
White, Andrew D., Ill, 30 *

White Leslie A., "Four Stages in the
Evolution of Minding," II, 239-53-
The Science of Culture, U, 303- men
tioned, n, 170, 172, 176, 179, 182 in
207-43 io-i. ui,

White, M. S. D., I, 525
White. W. A., n, 387

T?N-9 80 3133-0,

White dwarfs. See Stars

Wilberforce, Bishop Samuel, III, 29 30
40, 43

WiLLEY, Gordon R., "Historical Patterns
and Evolution in Native New World
Cultures," II, 111-41;
mentioned, II, 154, 174, 175, 176; III,
207-43 passim

Williams, G. C, I, 327, 329

Williams, R. C, I, 87

Williams, R. J., II, 387

Williamson, A. A., I, 312

Williamson, K., I, 598

Williston's law, I, 173 n.

Wilson, Jere, II, 395

Winkel, K., I, 110

Wisconsin glaciation, II, 60

Wissler, Clark, II, 325, 326, 327

Wittfogel, K. A., II, 161, 175

Woolley, Sir Leonard, II, 158

Wright, Sewall, "Physiological Genet-
ics, Ecology of Populations, and Natu-
ral Selection," I, 429-75;
mentioned, I, 315, 409, 417, 42'' 524
526, 529, 534, 536, 541; III, 107-43
passim

Writing: and early art styles, 11, 133; dat-
ing of, in New World, III, 227; function
of, m, 21 1; invention of, II, 85-86, 155

Wundt, W., n, 203

Xenophon, Memorabilia, II, 377

Yamey, B. S., Ill, 240

Yane. See Yin

Yen Fu: familiar with Huxley's work. III,

16; translated Evolution and Ethics into

Chinese, III, 16
Yerkes, Robert, II, 271
Yin and Yang: as components of the dual

power, m, 4; qualities of. III, 406

Zavarzina, N. B., I, 618

Ziehen, Th., I, 98

Zimmerman, E. C, I, 283, 524

Zinjanthropus: characteristics of, III, 157;
dating of, III, 163-65; derivation of,
n, 25; discovery of, II, 24-26; as man
in tool-making sense. III, 159; size of
brain in, HI, 157; significance of, to
human evolution, II, 26-29

Zirkle, Conway, II, 387-88

Zockler, Otto, III, 30

Zotterman, Y., II, 215

Zuckerman, S., Ill, 166

Library West / ALF

Date Due Slip

Date Due Date Returned

HAY 1 '6 imh

Online Renewal @ http://www.uflib.ufl.edu/

A fine of 25 cents per day is charged when this item is overdue.

. .

UNIVERSITY OF FLORIDA

3 Miimiii

3 1262 04839 2913

SCI-HSSL